Before you do that, did you perform you canned air cleaning earlier than you schedule?
In case you don't use canned air, google "How to clean laptop vents with canned air?"
I have an Acer Aspire 5742 - Windows 7 with Windows 8 partition. I'm not entirely tech savvy but I understand or at least know how to look up what I don't understand and can follow directions.
I use W7 and all files are saved on that partition. I figured I'd gottten a virus on 7 because programs were crashing and I was getting error messages getting progressively worse. I tried to back up the W7 files but the dvd program wouldn't recognize any discs I used. When I attempted to copy the files to a flash drive it would copy a few files then freeze. I was in safe mode in the middle of slowly getting the files on the flash drive with the intention of moving them to W8. I have a back up copy of W7 from June which I thought I could use when I needed it. I was afraid files after that date might be lost and I didn't want to take a chance since I've never restored from a back up before. W8 including the dvd writer and discs worked fine. On a side note, I updated W8 to 8.1 and installed a licensed version of Avast Internet Security to replace a trial that was expiring prior to starting this process. I don't know this might be important.
I was shutting down W7 each time it froze by pressing the on switch until it shut off then turning back on in W7. This last time instead of booting up I got the screen that said preparing to repair. Never having seen that before I now know it's a W8 screen. The dots circled but nothing happened and it eventually went to a black screen and stayed there up to the point I realized nothing more would happen.
Is there anything I can do to fix it? I can hit F2 and get set up on start up. I have discs for both programs. If I use one is there a repair option without wiping the hard drive? There are still files I wouldn't want to lose on W7.
Thanks so much for any help. Happy new year!