DONT do the upgrade. The breakages in outlook alone are legendary - huge issues with Activesync and Exchange connections.
It is another step on the path of losing functionality.
Crashes galorw with windows 10.
Try this to remove nag screen. Do the reg hack - stop office. Restart it or restart PC and try office again.
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Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\office\15.0\common\officeupdate]
"enableautomaticupgrade"=dword:00000000
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