Here's a great tip on file associations if you publish your virtual apps through a Citrix box. Thanks to Cesar Nunez for writing this up:
Issue: When publishing applications through Citrix Presentation Server 4.5, Content Redirection (File Type Associations) are automatically detected from the registry and you are presented with the list of available file types which can be associated with the various applications. When a SoftGrid enabled application is published through Citrix, Content Redirection does not list the associated file types.
Cause: For a local application, Citrix pulls the associated FTAs for an application from HKLM. SoftGrid stores this information in HKCU. Due to how SoftGrid delivers FTA information and how Citrix pulls the information for Content Redirection, Citrix is unable to successfully recognize which FTAs are associated with the SoftGrid enabled application and you are unable to manually add any new Content Redirection FTAs in the property pages.
Resolution: The following steps can be used to work around the issue:
1) Publish your SoftGrid applications on the SoftGrid Virtual Application Server, do not deliver FTAs to the client via SoftGrid.
2) After performing a SoftGrid Client refresh (logging in), manually create the necessary FTAs within the SoftGrid Client Management Console on the target Citrix client(s), checking the "Apply to all users" box in the 'Advanced' tab.
3) Once all the necessary FTAs have been added to the SoftGrid client as global FTAs per the above step, this information needs to be updated in Citrix from the registry by performing the next steps:
a. Open the Citrix Management Console (CMC).
b. Go to the 'Servers' node in the CMC, select the target server, right click, go to All Tasks and choose "Update File Types from Registry" from the context menu.
4) Create new Citrix published application for the SoftGrid enabled application(s) as normal.
5) Access the properties of the published application to set up the Content Redirection and you should now be presented with the list of SoftGrid enabled application File Types from which to choose from. Check all that apply and save the settings.
6) From a client with the PN Agent installed, refresh your applications.
7) Verify that documents associated to the new application have the correct icon.
8) Open both a document and the app directly to verify correct functionality.
More Information: SoftGrid FTAs are delivered on a per user basis, as the SoftGrid client refresh must be performed on a per user basis. In order to create global FTAs on a SoftGrid client, you would need to manually create the FTA within the SoftGrid Client Management Console and specify to "Apply to all users", which would store the FTA information in HKLM and allow Citrix to read the FTAs for use with Citrix Content Redirection.
J.C. Hornbeck | Manageability Knowledge Engineer