|See the info at Jolicloud's link.|
If you're doing that correctly......
I suspect the data in Windows or on your recovery partition that it needs is probably corrupted.
A common cause of that is the hard drive is in the process of failing.
Check your hard drive with the manufacturer's diagnostics.
See the latter part of response 1 in this:
If you don't have a floppy drive, you can get a CD image diagnostic utility from most hard drive manufacturer's web sites, but obviously you would need to make a burned CD, preferably a CD-R for best compatibility, on another computer if you need to.
Seagate's Seatools will test (almost) any brand of hard drive.
Do the long test.
The bootable Dos versions of SeaTools can be used even if Windows is not working properly.
If the hard drive itself tests okay, any data problems found can be fixed, one way or another..
If the hard drive itself is failing, you need to replace it, then load the orginal software from Recovery disks
If the hard drive itself is not failing, you probably still need to load the orginal software from Recovery disks,
Acer never includes Recovery disks for their recent or failrly recent computers with the system when it's new, but you can usually get the Recovery disk set for your model from their web site.
Pick your country.
I picked United States.
I chose this Top Answer
How do I reinstall the Operating System on my computer?
Click on the blue link for: Acer Recovery Media Order Form in this:
"If the ability to reinstall from the previous method is not available or fails, recovery of the Operating System will need to be from Recovery Media. If you do not have a set of Acer Recovery Media, you may purchase the set online from the Acer Recovery Media Order Form."
If Acer does not have the Recovery disks, there are a small number of web sites that have collected the Recovery disk sets for brand name computers.
If they don't list your exact model, if you contact them, they MAY be able to provide with them - e.g. the same disks may be used for several or many models made by the brand at about the same time.