PROBLEM:
You open a Revit project and get messages that linked Revit files are corrupt.
CAUSE:
The drive C on your computer doesn't have enough free space.
SOLUTION:
Exit Revit.
Delete as much as you can from your drive C.
Run Disk Cleanup (Start button bottom left of desktop, All Programs > Accessories > System Tools)
Restart Revit.
If this doesn't work try deleting some user profiles.
In Drive C, Users folder. Delete some user folders (but don't delete Public or your own folder).