Hi,
Since it says there is a .pst problem, I suggest you run Scanpst.exe to scan and repair the .pst file. The location of Scanpst.exe depends on your Outlook and Windows version:
Outlook 2013
32-bit Windows C:\Program Files\Microsoft Office\Office15
64-bit Windows C:\Program Files (x86)\Microsoft Office\Office15
64-bit Outlook C:\Program Files\Microsoft Office\Office15
Click-to-Run C:\Program Files\Microsoft Office 15\root\office15
Outlook 2010
32-bit Windows C:\Program Files\Microsoft Office\Office14
64-bit Windows C:\Program Files (x86)\Microsoft Office\Office14
64-bit Outlook C:\Program Files\Microsoft Office\Office14
Outlook 2007
32-bit Windows C:\Program Files\Microsoft Office\Office12
64-bit Windows C:\Program Files (x86)\Microsoft Office\Office12
If the problem persists after repairing with Scanpst.exe, I need to know more information:
1. What kind of repair dialog box was it? What did it try to repair?
2. You mentioned you are using a Gmail Calendar, how did you set it up in Outlook? With Google Apps Sync for Microsoft Outlook?
Generally Gmail users choose IMAP or POP in Outlook, which don't support Calendar sync. If you are using some 3rd-party tools to sync the calendar and now having some problems, I can provide limited information on my side. I suggest you contact the
developer of the tool to get more dedicated support.
Feel free to let me know more details if I misunderstand anything.
Regards,
Melon Chen
TechNet Community Support