If you go to file manager, right click your file and click "Edit file summary" - do you see "Alias" as an editable field?
Look in your filesummary.config file (in the root of your project). The nodes under <model><instance> are the "dictionary" used as editable fields for your files.
Is there a node called "Alias" under <model><instance> ? If not, add it.
More information about filesummary.config here http://www.frederikvig.com/2010/04/episerver-file-manager-and-file-summary/
I'm working on a site that recently has been migrated from CMS 5 to CMS 6 R2. There is a dynamic function for listing files (in VPP). It's working the way it used to work but somehow it doesn't display the file metadata. Right now it's listing the filename instead of the file description (default if no description - use file name instead). In the current code it's refering to Summary.Dictionary["Alias"]. I've tried to change this to Description and even Author. The metadata is there but it doesn't show in the list. Is there some kind of config setting that's missing perhaps? Thankful for help!