Hi whatsup,

Thanks for leaving the message.
I would say your troubleshooting methodology is absolutely making sense. But that's not the case - as I said, no newly installed/uninstalled software, no OS configuration changes, no Windows Office Update and no nothing but launched a few applications processes.

Yesterday I did another image restoration and checked the issue "hasn't happened yet", and I disabled Teamviewer to start up with Windows and make sure no Teamviewer background service running. That's because I realized each time the issue happened when I sit in office using Teamviwer to remotely control my PC. Considering I've been using Teamviewer for a while and the issue didn't happen until the very first time I did copy/cut/undo operations via Teamviewer, so for now I'll keep Teamviewer installed but stop all of its processes and services.

It's been a few hours and I can normally do copy/cut/undo in my Excel 2010 x64. I'll feedback here once it's stable for, say, 2 weeks, OR, the issue happened without Teamviewer.

Why using x64 ? Because Microsoft developed it, and many many more reasons.