I'm not sure what happened but i'll do my best to explain it. Let me know if you need any more info.
I have a hp dv6500 vista home premium laptop. I clicked restart just before closing my laptop. When i opened it up it gave me the warning saying the battery was low and to plug it in before proceeding to risk losing any data. So i plugged it in. When i logged onto my computer all of the files i had saved on my desktop and my documents were gone. I just coudn't figure out what happened. At this point i noticed Windows Live One Care was running some updates, but otherwise the computers desktop appeared to be reset to default standards (all my installed programs were still present just not any documents), my widgets were all missing, etc. I had some school work to do and no time to mess with it so i quickly typed something up. Later when i restarted my computer it was back to normal. Now... the document which i typed when the comp was having problems is missing. I did a quick search through the c: drive. I found one instance of a file with the same name but it had a weird file type and had a size of 0bytes. Unfortunately i can't tell you what the file type was b/c i went back to look 5 min later and the file no longer exists, i had found the file with the strange file type in the TEMP file through the search function.
Sorry for the long post but i wanted to give you as much info as possible so that you might be able to help me understand what is going on. I appreciate any help or advice you may be able to offer.
Sorry. It is a bit of a stumper. I can only make a few general suggestions:
So you got 2 problems? You'd like to get the file back and why the heck is this happening? Or is the file no longer important?
Search for *.bak and see if your file shows up.
Something is messing up, could be a hard drive issue or a corrupt Windows install, maybe a RAM issue.
I'd run chkdsk on your hard drive and memtest86 on the RAM. Chkdsk might get your file back but it may show up as a randomly numbered file.
If you installed something recently which preceded this fiasco you might try uninstalling it or else running 'system restore'.
If nothing seems to help you might want to just do a 'repair install' off the Vista DVD. Maybe something got scrambled on Vista during that period when the power was low. A repair install might fix it. If not do a fresh install.
Are you making your laptop 'sleep' or are you shutting it down? I have noticed that if the PC loses power during sleep, it will sometimes do very strange things (this also includes low battery). Including not saving files to the hard disk even when you explicitly save it manually.
The only reason I know this is that I downloaded a program and put it on the desktop for later. Made a text file and saved it (clicked the 'X' then click 'Yes' then 'OK' for untitled.txt). It went to sleep, we had a short moment of no power, common in this area. After restarting the computer both files were gone with no trace of them, even after searching... and my Crysis install was corrupted - no clue whats up with that. Maybe the superfetch has something to do with it.
If you are shutting it down or hibernating it, I have no clue about that.
I personally recommend just shutting down your laptop or using hibernate instead of sleep. But for most desktop PC's its usually fine.