Windows 7 - Keyboard - Shift & Alt keys stopped working for keyboard shortcuts

As I wrote in the title, my Shift and Alt keys stopped working for keyboard shortcuts. However, the Shift key still works when capitalizing letters.

I've been dealing with this problem off/on for the past two weeks and haven't been able to figure it out. I've gone into Ease of Access features and turned on/off all of the available options (Mouse Keys, Sticky Keys, Toggle Keys, Filter Keys). I've pressed Shift for 8 seconds, and pressed it 5 times, and still haven't been able to correct it.

Thank you in advance for any help offered.



Possibly helpful additional information:

• I've got a Spanish/Latin American keyboard layout installed in addition to the US English keyboard layout. I toggle back and forth with Left Alt + Shift (which is how I noticed my Shift key stopped working).
• I play a game whose controls rely on a lot of Shift key pressing and holding.

When was the last time you used a can of air cleaner on the keyboard? If it isn't from contact wear often keyboards tend to get loaded up with dust and debris!

One example of that is having any snacks onhand around a pc where little bits get passed along from your fingers onto and under the keys themselves. Keyboards are known to get loaded up fast with any foods present!

I haven't used air cleaner on my keyboard yet (have had it for 6+ months), but I'll pick some up this weekend and try it. I'll check back in with the results. Thanks for the suggestion!

Tried the compressed air and got a whole bunch of dust and crap out, but keyboard is still not working properly. D'oh!

Well now you can see how keyboards are notorious collectors!

For the shift and alt key combo having problems with one key you are now likely looking at a bad contact. With everything cleaned out you are most likely looking at wear since you use that key in gaming.

Without realizing it most tend to press down harder on keys assigned to movements especially in 1st person shooter games then at any other time. This unfortunately can take a toll on things like the individual contacts depending on the quality of the keyboard being another factor.