Project Server Problem - Corrupted Cache

Problem
Some time we face following problems when we try to edit /open a project in Project professional-

• "Not able to edit project, Check-in Pending state" : this problem is typically caused by a project manager publishing his or her project, then closing the project before Project Professional 2007 completes the publish operation. It can also occur if a project is closed and an attempt is made to reopen it prior to the completion of the initial close process.
• “Custom fields’ lookup tables are scrambled.” : when there are multiple Project Server accounts on a machine, the Enterprise Global template is undergoing frequent modification, and the cached version of the Enterprise Global template becomes corrupted.

Solution
we can resolve both issues by taking one of two approaches:

• Performing a Project Cache cleanup operation from within Project
  Professional,
• Deleting all of the folders that reside under the folder C:\Documents and
  Settings\USERNAME\Application Data\Microsoft\MS Project\Cache.

You should close Project Professional before performing this operation. By doing so, you bypass the benefits of performing only an incremental open of the project, and force Project Professional to transfer the full project file (Full Open) the next time it is opened.