Unable to launch project files from web pages with Microsoft Project published with Citrix XenApp 6.5

Problem

When you attempt to open a Microsoft Project file from a link either on a webpage or SharePoint site, you receive the following error:

Project cannot open the file.

Check that the file name and path are correct.

Check that the file format is recognized by Project.

Project files saved in a version earlier than Microsoft Project 98 can’t be opened.

If your file is from an earlier version, open it in that version, click Save as (File menu) and save in MPX format.  Open the MPX file in the current version of Project. When you use this method, project data is imported, but formatting is lost.

Solution

One of the reasons why you would encounter this error when opening Microsoft Project files with Microsoft Project published via Citrix XenApp is because of how MS Project handles opening files through a browser.  When Citrix XenApp attempts to open the Microsoft Project, it actually needs to temporarily download the file in the user’s temporary internet files folder then launches the file.  Since the web browser is located on the user desktop and the MS Project application is located on the server, the temporary file is going to be stored on the C drive of user’s desktop and the Citrix XenApp server has no way of accessing that file.  The solution is to change the temporary internet files folder to a common drive that is accessible via the local desktop and the XenApp server (i.e. the user’s home drive).