Why my Outlook cannot sync with Exchange?
The Outlook pst file could be corrupted. To fix it:
1. Close Outlook.
2. Open Windows Explorer and go to c:\program fiels\Microsoft Office\Offic 12(your version of office might be 11, 10, or 9)
3. Look for scanpst.exe and double click it to run
4. The program will ask you to enter the name of the file you want to scan. On Windows 7 or Vista, it is in C:\Users\[username]\AppData\Local\Microsoft\Outlook. On XP, it is in C:\Documents and Settings\\Local Settings\Application Data\Microsoft\Outlook.
5. After you have enter or browse the location and file, hit run.