iMac Running Yosemite Locks Up

[Tucom]

Running a heavily used 2009 27 iMac, with 16GB RAM, i7, and a Crucial MX100 SSD. The Mac just COMPLETELY locked up. Only the mouse would work, though the cursor wouldn't change appropriately dependent upon what was being hovered over on screen.

Had a few Safari tabs open, Xcode, iBooks, Mail, and Activity Monitor. Never did this before. Running Yosemite. Had to hold down power button to turn off then turn back on; even Command + Option + Esc didn’t work.

Any ideas? Anyone else have this happen, if not even on Yosemite or on a Mac other than an iMac?

 

[Tucom]

I think I figured out what the issues was -

I had Intego X8 installed, and as other people reported, that evidently can make certain Macs totally lock up.


Hope this helps anyone else.