I have disabled some add-ons that I think unnecessary for me which fixed the problem for me.
COM Addin for Microsoft Office Outlook Connector
Microsoft Office SharePoint Server Colleague Import Add-in
Microsoft Outlook Mobile Service
Here is how to disable them.
- Go to Trust Centre as below.
- Go to Add-ins
- Go to Manage, select COM Add-ins and click on Go (As circled in above picture).
- Remove ticks from above mentioned add-ins as in following image and click on OK.
- Restart Outlook 2007.