Hi

Looks like some settings in episerver.config is not setup correct. Check attribute uiUrl and utilUrl of the siteSettings tag and virtualpaths of the providers under virtualPath tag in episerver.config.

It should look something like this:

<siteSettings uiUrl="~/myUI/CMS/" utilUrl="~/util/" ...../>

<add virtualPath="~/App_Themes/Default/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\App_Themes\Default" name="App_Themes_Default" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add virtualPath="~/myUI/CMS/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\UI\CMS" name="UI" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add virtualPath="~/Util/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\util" name="UtilFiles" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add virtualPath="~/WebServices/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\webservices" name="WebServiceFiles" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add virtualPath="~/myUI/CMS" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\UI\EPiServer\CMS" name="EPiServerCMS" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add virtualPath="~/myUI/Shell" physicalPath="C:\Program Files (x86)\EPiServer\Framework\6.2.267.1\Application\UI" name="EPiServerShell" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />

Regards

Oskar

Thank you Oskar. I have compare the episerver.config and looks the same as you posted. Following is my episerver.config

<episerver xmlns="http://EPiServer.Configuration.EPiServerSection">
  <!-- connectionStringName:              Name of the connection string (one of the named strings in <connectionStrings> section) to use for
                                          the EPiServer database. If not defined it will default to EPiServerDB -->
  <!-- enableScheduler:                   Set to false to disable EPiServer's connection with the scheduler. Default value (if the tag does
                                          not exist) is true. -->
  <!-- errorMailHandler:                  Set the relative adress to the page that should handle the posts from the handled error page. -->
  <!-- globalErrorHandling:               Set whether to use EPiServer's error handling. ( RemoteOnly, On, Off )-->
  <!-- globalErrorMail:                   E-mail address that error messages should be sent to. -->
  <!-- httpCacheExpiration:               Change this value to set the number of seconds a page should be cached, this value will be set in
                                          the http request policy. It will activate both client side caching and server caching (outputcache).
                                          Policy will only apply to anonymous users and when http request method is GET. The cache will
                                          automatically be updated when changes are made to a page in EPiServer. Recommended setting is 1 hour -->
  <!-- httpCacheability:                  Change this value to modify the cacheability of pages when using output caching. I e only used when
                                          httpCacheExpiration is set to a non-zero value. Use values from the System.Web.HttpCacheability enumeration. -->
  <!-- httpCacheVaryByCustom:             The custom values the browser should vary by -->
  <!-- httpCacheVaryByParams:             The parameters to the page(ie querystring) that the cache should vary by-->
  <!-- indexingDelayAfterPublish:         Delay time between publish and indexing. -->
  <!-- indexingTextRegExp:                The regular expression to index words in pages. -->
  <!-- indexingTextEnabled                If indexing of text into keywords should be enabled -->
  <!-- logServiceUrl:                     URL to the log service. -->
  <!-- mirroringFileWriteRetryDelay:      Time until next retry of file write. -->
  <!-- mirroringHtmlTextEncoding:         Sets which encoding should be used when mirroring to HTML. -->
  <!-- mirroringRetries:                  Number of retries when a mirroring job fails. -->
  <!-- mirroringRetryDelay:               Time until next retry. -->
  <!-- pageCacheSlidingExpiration:        Page cache interval for local database, set to 0 to disable -->
  <!-- pageUseBrowserLanguagePreferences: Used prefered languages from browser as GUI language. -->
  <!-- pageValidateTemplate:              Sets if the current template has to match the page type template (true|false). -->
  <!-- remoteCacheListenerShortNames:     A comma-separated list of remote sites that will receive cache notification when a change is made
                                          on this installation. Only enter the short name, the definition of url etc is made in admin mode
                                          under Remove sites. Useful for web farms scenarios, and other when data is shared. -->
  <!-- remotePageCacheSlidingExpiration:  Page cache interval for remote sites, set to 0 to disable -->
  <!-- remoteWebServiceCulture:           Set the System.Threading.Thread.CurrentThread.CurrentCulture if handling pages remote. -->
  <!-- sgmlParserDecodeCharEntities       Optional value indicating whether SgmlParser should decode character entities (like "&#32;" will be decoded as space). -->
  <!-- siteDisplayName:                   The name of the site. -->
  <!-- stringCompressionThreshold:        Set to the number of characters when compression should be activated. -->
  <!-- stringDelayedLoadThreshold:        The number of characters when delayed loading should be activated for large strings in properties
                                          deriving from Long String.-->
  <!-- subscriptionHandler:               Defines which class should handle mail. -->
  <!-- uiDefaultPanelTab:                 The index of the EditPanel tab that is to be shown by default when clicking a page in the editmode
                                          pagetree. -->
  <!-- uiEditorColors:                    Defines the name and value of colors that should be available for the editors. -->
  <!-- uiEditorCssPaths:                  Defines which css file(s) to use when rendering the editor. -->
  <!-- uiEditorHeight:                    Defines the height of the editor in edit mode. -->
  <!-- uiEditorValueOptions:              Setting for use of DIV tags or P tags. -->
  <!-- uiEditorWidth:                     Defines the width of the editor in edit mode. -->
  <!-- uiEditorUnformattingPersistedTags: Defines which tags that should be preserved during Remove Format operation. -->
  <!-- uiImageTransparencyReplacement:    The color that should replace the transparent color in a picture compression. -->
  <!-- uiKeepUserLoggedOn:                Sets if the current windows authenticated user must reauthenticate after session timeout. -->
  <!-- uiOptimizeTreeForSpeed:            Set to true if page tree controls should not evaluate if tree nodes have children. -->
  <!-- uiSafeHtmlTags:                    Set which tags should not be encoded, Example format is: b,i,u,br -->
  <!-- uiShowGlobalizationUserInterface:  Defines if the globalization user interface should be used. -->
  <!-- operationCompatibility:            Defines the operation compatibility which make data factory treats as old semantic. The operationCompatibility attribute can have None, Save, Delete or
                                          Full value or you can altso combine them.(e.g Save,Delete).-->
  <!-- uiTheme:                           Application visual layout theme name. -->
  <!-- urlRewriteExtension:               Defines an extension that is mapped to ASP.NET for the URL. -->
  <!-- urlRebaseKind:                     Defines the type of rebasing performed by the HTML rewriter, i e if the URL should be relative (the default), or root relative.
                                          Possible values are: ToRelative, ToAbsolute, IgnoreRootRelative and NoLeadingDotDot. The values can be combined using comma as a separator (for example "IgnoreRootRelative,ToRelative") -->
  <!-- workflowDelayedLoading:            States if workflow definitions and instance metadata should be loaded at application initialization
                                          (false) or at first request of workflow data (true). Default is false.-->
  <!-- episerver:                         By moving a section to an external file, it is possible to make changes in the external file without restarting
                                          the site. As for all sections, this is also possible for the episerver section. To move the section, create a new
                                          configuration file and copy the whole episerver section to that file. Then remove the section in this file and
                                          add this line insted: <episerver configSource="episerver.config" /> (change episerver.config to the filename).
                                          If you want to make changes in the new external file without restarting the site, add the attribute "restartOnExternalChanges"
                                          in the section header (below configSections) for the episerver definition. Set the value for the attribute to false.
  -->
  <workflowSettings workflowDelayedLoading="false">
    <workflowHost type="EPiServer.WorkflowFoundation.AspNetWorkflowManager,EPiServer.WorkflowFoundation" />
    <definitions>
      <definition name="Sequential Approval" description="A sequential approval workflow for pages" type="EPiServer.WorkflowFoundation.Workflows.SequentialApproval,EPiServer.WorkflowFoundation" />
      <definition name="Parallel Approval" description="A parallel approval workflow for pages" type="EPiServer.WorkflowFoundation.Workflows.ParallelApproval,EPiServer.WorkflowFoundation" />
      <definition name="Request for feedback" description="Assigns request for feedback tasks to users/roles" type="EPiServer.WorkflowFoundation.Workflows.RequestForFeedback,EPiServer.WorkflowFoundation" />
      <definition name="Ready for translation" description="Assigns translation tasks to users/roles" type="EPiServer.WorkflowFoundation.Workflows.ReadyForTranslation,EPiServer.WorkflowFoundation" />
    </definitions>
    <externalServices>
      <externalService type="EPiServer.WorkflowFoundation.Workflows.ApprovalService,EPiServer.WorkflowFoundation" />
      <externalService type="EPiServer.WorkflowFoundation.Workflows.ReadyForTranslationService,EPiServer.WorkflowFoundation" />
      <externalService type="EPiServer.WorkflowFoundation.Workflows.RequestForFeedbackService,EPiServer.WorkflowFoundation" />
    </externalServices>
  </workflowSettings>
  <sites>
    <site siteId="MyEPiServerSite2" description="Example Site">
      <siteSettings enableScheduler="true" errorMailHandler="~/util/SendErrorReport.aspx" globalErrorHandling="RemoteOnly" globalErrorMail="" httpCacheExpiration="0:0:0" httpCacheability="Public" httpCacheVaryByCustom="path" httpCacheVaryByParams="id,epslanguage" indexingDelayAfterPublish="0:0:20" indexingTextRegExp="[\p{N}\p{L}]{1}[\p{N}\p{L}-\._]*[\p{N}\p{L}]{1}" logServiceUrl="soap.tcp://localhost/TimeSpanAnalyzerView" mirroringFileWriteRetryDelay="0:0:5" mirroringHtmlTextEncoding="" mirroringRetries="5" mirroringRetryDelay="0:0:1" pageCacheSlidingExpiration="12:0:0" pageFolderVirtualPathProvider="SitePageFiles" pageOfficeStartId="0" pageRootId="1" pageStartId="3" pageUseBrowserLanguagePreferences="false" pageValidateTemplate="false" pageWastebasketId="2" remoteCacheListenerShortNames="" remotePageCacheSlidingExpiration="2:0:0" remoteWebServiceCulture="0" sgmlParserDecodeCharEntities="false" stringCompressionThreshold="0" stringDelayedLoadThreshold="0" subscriptionHandler="EPiServer.Personalization.SubscriptionMail,EPiServer" uiDefaultPanelTab="0" uiEditorColors="" uiEditorCssPaths="~/Templates/AlloyTech/Styles/Default/Editor.css" uiEditorHeight="250" uiEditorValueOptions="0" uiEditorWidth="500" uiImageTransparencyReplacement="White" uiKeepUserLoggedOn="true" uiMaxVersions="0" uiOptimizeTreeForSpeed="false" uiSafeHtmlTags="b,i,u,br,em,strong,p,a,img,ol,ul,li" uiShowGlobalizationUserInterface="true" uiTheme="" uiVersionMerging="true" urlRewriteExtension="" urlRebaseKind="ToRootRelative" operationCompatibility="None" siteDisplayName="Alloy Technologies" siteUrl="http://localhost:9501/" uiUrl="~/episerver/CMS/" utilUrl="~/util/" enableXmlRpcHeader="true" />
      <pageGuides>
        <pageGuide destinationPageId="41" name="News" pageTypeName="[AlloyTech] News item" title="Create news item">
          <visibleProperties>
            <pageProperty propertyName="PageName" />
            <pageProperty propertyName="MainIntro" />
            <pageProperty propertyName="Author" />
            <pageProperty propertyName="MainBody" />
          </visibleProperties>
        </pageGuide>
      </pageGuides>
    </site>
  </sites>
  <!--*** NOTE ***
    All virtualPath providers must have a matching <location><system.web><httpHandlers> section according to the following pattern:

    <location path="Documents">
      <system.web>
        <httpHandlers>
          <add path="WebResource.axd" verb="GET" type="System.Web.Handlers.AssemblyResourceLoader" validate="true" />
          <add path="*" verb="*" type="EPiServer.Web.StaticFileHandler" validate="true" />
        </httpHandlers>
      </system.web>
    </location>
    
    The location path matches the virtualPath settings of the <add> element, i e a virtualPath="~/Documents/" translates to <location path="Documents">.
    -->
  <virtualPath customFileSummary="~/FileSummary.config">
    <providers>
      <clear />
      <add showInFileManager="true" virtualName="Page Files" virtualPath="~/PageFiles/" bypassAccessCheck="false" name="SitePageFiles" type="EPiServer.Web.Hosting.VirtualPathVersioningProvider,EPiServer" indexingServiceCatalog="Web" physicalPath="C:\EPiServer\VPP\MyEPiServerSite2\PageFiles" />
      <!--<add showInFileManager="false" virtualName="Virtual Path Mappings" virtualPath="~/upload/"
            bypassAccessCheck="false" name="SitePathMappings" type="EPiServer.Web.Hosting.VirtualPathMappedProvider,EPiServer" />-->
      <add showInFileManager="true" virtualName="Global Files" virtualPath="~/Global/" bypassAccessCheck="false" name="SiteGlobalFiles" type="EPiServer.Web.Hosting.VirtualPathVersioningProvider,EPiServer" indexingServiceCatalog="Web" physicalPath="C:\EPiServer\VPP\MyEPiServerSite2\Global" />
      <add showInFileManager="true" virtualName="Documents" virtualPath="~/Documents/" bypassAccessCheck="false" maxVersions="5" name="SiteDocuments" type="EPiServer.Web.Hosting.VirtualPathVersioningProvider,EPiServer" physicalPath="C:\EPiServer\VPP\MyEPiServerSite2\Documents" />
      <!--
        <add showInFileManager="true" virtualName="Global Files" virtualPath="~/Global/"
          bypassAccessCheck="false" indexingServiceCatalog="Web" physicalPath="%EPISERVERFILESDIR%\EPiServerFiles\Globals"
          name="SiteGlobalFiles" type="EPiServer.Web.Hosting.VirtualPathNativeProvider,EPiServer"
          WriteAccess="Administrators" DeleteAccess="Administrators" />
        -->
      <add name="App_Themes_Default" virtualPath="~/App_Themes/Default/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\App_Themes\Default" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add name="UI" virtualPath="~/episerver/CMS/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\UI\CMS" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add name="UtilFiles" virtualPath="~/Util/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\util" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add name="WebServiceFiles" virtualPath="~/WebServices/" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\webservices" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add name="EPiServerCMS" virtualPath="~/episerver/CMS" physicalPath="C:\Program Files (x86)\EPiServer\CMS\6.1.379.0\application\UI\EPiServer\CMS" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
      <add name="EPiServerShell" virtualPath="~/episerver/Shell" physicalPath="C:\Program Files (x86)\EPiServer\Framework\6.2.267.1\Application\UI" type="EPiServer.Web.Hosting.VirtualPathNonUnifiedProvider,EPiServer" />
    </providers>
    <filters />
  </virtualPath>
  <!-- virtualPathMappings are used by "VirtualPathMappedProvider". -->
  <virtualPathMappings>
    <!--<add url="~/ExternalSample.ascx" mappedUrl="~/MappedSample.ascx" />-->
  </virtualPathMappings>
  <urlRewrite defaultProvider="EPiServerFriendlyUrlRewriteProvider">
    <providers>
      <add name="EPiServerFriendlyUrlRewriteProvider" description="EPiServer standard Friendly URL rewriter" type="EPiServer.Web.FriendlyUrlRewriteProvider,EPiServer" />
      <add name="EPiServerIdentityUrlRewriteProvider" description="EPiServer identity URL rewriter" type="EPiServer.Web.IdentityUrlRewriteProvider,EPiServer" />
      <add name="EPiServerNullUrlRewriteProvider" description="EPiServer bypass URL rewriter" type="EPiServer.Web.NullUrlRewriteProvider,EPiServer" />
    </providers>
  </urlRewrite>
  <imageEditor windowWidth="900" windowHeight="600" enabled="true">
    <sizePresets>
      <preset width="320" height="240" />
      <preset width="640" height="480" />
    </sizePresets>
  </imageEditor>
  <dynamicContent>
    <controls>
      <add description="Map dynamic content" name="MapDynamicContentDemo" type="EPiServer.Templates.AlloyTech.DynamicContent.MapDynamicContent, EPiServer.Templates.AlloyTech" />
    </controls>
  </dynamicContent>
  <pageProvider>
    <providers>
      <!--<add name="ResellersExcelPageProvider"
               type="EPiServer.Templates.Advanced.PageProviders.ExcelPageProvider, EPiServer.Templates.AlloyTech"
               entryPoint="{EntryPoint}"
               filePath="~/Templates/Advanced/PageProviders/ExcelPageProviderSource.xlsx"
               idColumn="ResellerID"
               pageName="ResellerName"
               pageTypeName="[AlloyTech] Reseller"
               sheetName="Resellers"
               capabilities="None"/>-->
    </providers>
  </pageProvider>
</episerver>

Have you checked if the CSS problem only occurs while you access EPiServer edit/admin or it doesnt load css in rest of the site  . If everything else is correct check the StaticFileHandler just in case if that went missing.

Check if http://localhost:9501/episerver/cms works. If not check if the isapi wildcard mapping is set correctly.