This is NOT the OS SAFE MODE. Link follows.
My outloook 2010 was working just fine until I did not use my computer for about an entire month. I switched off my notebook and did not get around to using it for a whole month. When I started to use my HP notebook with Windows 7, Outlook would start just fine but hang as soon as I clicked on anything (email, tab, options anything). It gave me the Outlook is not responding, close the program or restart error. If I just open Outlook without touching anything, it would get stuck during send/receive. I have noticed this new gear icon on the bottom right next to send/recieve which on a mouse hover says 'Data file check in progress'. I tried starting it in safe mode (Outlook /safe) with the same results. Another odd thing I have recently noticed is a random pop up which says my appointments could not be synced (I have Google calendar Sync installed). A general occurence (even before this issue) is that my reminders would randomly pop up at regular intervals on my desktop even when Outlook was completely shut down (this still happens). I have tried the scanpst utility and it gave some errors, I scanned and repaired this file but with no improvement. I have not installed or removed any new programs since. (I started Outlook as soon as I switched on my computer).I have also tried repairing Microsoft Office via the uninstall programs feature.