Problem: Keyboard acts like ctrl key is stuck on, but not physically depressed. Press s and get the save dialog box, etc.
Band-aid Solution: Bring up on-screen keyboard and the problem disappears until next log-in.
Solutions tried: After much googling and tinkering, many possible solutions were presented. The problem doesn't seem to be specific to Acer, nor the Windows version.
The following steps have been attempted.
1) Tried function key with many variables. Fail
2) Tried external keyboard, which worked most of the time but not always. Fail.
3) Tried uninstalling keyboard and letting Windows reinstall. Fail.
4) Tried full system restore to factory defaults. Fail
5) Booted to USB drive running Linux Mint -- Keyboard works fine, indicating it must be a software issue in the Windows 7 configuration. A Clue.
6) Removed Synaptic touchpad drivers. Fail.
7) Reinstalled Synaptic touchpad drivers and disabled pinch zoom. Fail.
8) Disabled sticky keys. Fail.
9) Removed ALL software except for drivers provided by Acer. Fail.
I think I may just replace the hard disk with a solid state drive and install Linux Mint. However, I'd like to get this issue sorted for two reasons.
1) I don't like conceding to a damned computer.
2) I will most likely sell the unit and that will be much easier to do if it's running Windows and if it's working properly.