Whilst cleaning my laptop I pressed the ON button accidentally and because I didn't have time to wait for it to boot, I forced it to shut down down again (pressed and held said button for ~ 8 seconds). On the next boot, the system did a CHDSK. I thought it wouldn't hurt, so I let it. Ever since, I am missing a folder of several GBs on my second partition (not the one with the system on). Is there any way I can recover the lost data?

Restore your data from a recent backup. An expenisve data recovery company. I know of no other way. The deletions by check disk were bad blocks on the drive and may not have been accessible had the system booted normally anyway. The utility doesn't randomly delete files, it attempts to make it readable first, and then deletes it. The forced power cycling may have damaged the hard drive as well as the data. You should download the drive utility from the drive manaufacturer and check the drive And, as you have learned, unplug and remove the battery when working on a laptop to remove the power.

Well there was nothing wrong with my drive. There were no errors and YET it still randomly deleted files off a partition the system does not even need. I found recuva, which brought some of it back so far. Doing a deep-scan right now, so I might find more. There should ALWAYS be another way...: http://www.piriform.com/recuva

Do a file search for *.chk files probably on the C:\ drive. Jerry