Some programs automatically got uninstalled help pls

[JoeKkerr]

Win7 64 bit with AVG protection

Last night i played my game of dota 2 and went to sleep after some facebook , this morning i turned on the pc & saw i didnt had my primary browser firefox, the shortcut showed blank and when accessed it asked to be deleted as it was blank
I pressed delete and reinstalled Firefox , few minutes later i clicked on start menu & to my surprise Steam, Audacity, Photoshop all were gone, i went to the installed folders but they werent there

Im on my way to reinstall those but i need to know why that happened, could someone please help me , i tried googling.

[DaveLembke]

Does anyone else have access to your computer who may have uninstalled them on you?

Any error messages when logging on? I have seen before a corrupt profile cause a default profile to load that is lacking and it gives you a temporary profile.

[JoeKkerr]

No one did...im the first one to turn on and off the pc
Yea i get a error message at startup title says autoit error and inside that chromeax3 or something but this
Was prevIling even before these...
Today things are worse slowly all my system drivers are uninstalled im typing this from my tablet because
My network adapter drivers are deleted constantly getting blue screen of death randomly.....y mouse and keyboard have decided to work randomly

The is is a fresh copy of windows i installed few months back

[DaveLembke]

Degradation sounds like corruption where data is getting orphaned. Hard Drive might be ill. Do you have a image or system recovery media or original windows OS installation DVD to perform a clean build? Then run crystaldiskinfo to check hard drive health.http://crystalmark.info/download/index-e.html