I am user office 365 and have an excel spread sheet. when I try to insert the MonthView in the worksheet I get "Cannot Insert Object".

Hi AZCowboy,

Based on your description, I suggest you refer to these articles about the error "cannot insert object":

http://blogs.technet.com/b/the_microsoft_excel_support_team_blog/archive/2014/12/11/forms-controls-stop-working-after-december-2014-updates-.aspx

https://support.microsoft.com/en-us/kb/3025036

You can also try this method:
Quit all Office applications.
Start Windows Explorer.
Enter %temp% in the address bar, then press Enter.
Use the Search box to search for *.exd
Delete all found files.
You can also open the following folders within the Temp folder and delete the .exd files in them:
- Excel8.0
- VBE
- Word8.0
Restart Windows.

Hope it's helpful.

Regards,

Emi Zhang
TechNet Community Su