Issue with browsing files in browser having special characters in file name and fix

After upgrading one of our very old customer’s website from EPiServer 4.62 to CMS 6 R2, it was reported that documents with special characters in file name (for e.g. ‘S&R12.pdf’) throwing ‘System.Web.HttpException: A potentially dangerous Request.Path value was detected from the client (&).’ when they are being opened up in browser.

Fix for this is issue is to just add requestPathInvalidCharacters="" if you want to allow all special characters.

The above attribute must be added to the element <httpRuntime> in your website’s web.config so that it will look as follows:

<configuration>

    .

    .

    <system.web>

        .

        .

        <httpRuntime requestValidationMode="2.0" requestPathInvalidCharacters="" />

        .

        .

    </system.web>

    .

    .

</configuration>

If you want to restrict certain special characters then make sure you specify them as requestPathInvalidCharacters="&lt;,&gt;,*,%,:,&amp;,\"