One of our customers has a SharePoint 2007 document library for storing Crystal Reports. As well as being available directly, a link is also published via Citrix (Presentation Server 4.5). This has worked without problems for a few years.
Recently, the SharePoint sites were migrated to a new server running SharePoint 2010 and the Citrix link was updated to account for this. Now many users are seeing "Loading" where each document should be. This happens with other document libraries also.
If the user changes the URL so that it points back to the old server, the documents load normally. Anyone connecting directly via their desktop browser does not experience any problems either. There are also no problems for someone if they RDP onto the Citrix server and run the browser from there. The issue only occurs for users accessing SharePoint via Citrix, and even then, not in every case.
The SharePoint server doesn't seem to be at fault because when not going through Citrix, the page loads correctly. IE settings don't appear to be the problem because the identical page on the old server loads without any problems. That leaves Citrix looking like the most likely culprit, but again, Citrix serves up the old page without any issues, only having a problem with the version on SharePoint 2010, and even then there are some users having no problems at all.