Flash Drive Problem - Files corrupted after eject

I have a pretty new computer, Windows 7 Pro 64-bit, but I've had nothing but trouble with it. I've already had the hard drive replaced due to failure, (at least it's still under warranty). But now I'm having flash drive problems. If I backup my files to a flash drive using GoodSync, everything is fine, but if I Copy/ Paste a few files to a flash drive, not for backup, but just to work on those files in another computer, they get corrupted. I check the files after I paste them, and they are OK, but after ejecting the drive (the right way), and then trying to access the files in another computer, they can't be opened. It happens the most on one particular flash drive, but I've also had it happen on other drives as well. This problem I had when I moved a few files from my defective hard drive before sending it to HP (all the rest of the files I had already backed up, and they are OK), but after I got it back, it was OK for a while, and now it's doing it again. I checked the Event Log, and there were no error messages related to the flash drive. The only error messages there were from Windows Media Player Network sharing Services, which I have now disabled.
I dont' know if Win7 Pro is a lot more buggy than Home Edition, but my old laptop I had for almost 5 years with Home Edition, and never had any problems, except for the DVD drive failing. This one has been giving me nothing but grief. It seems to work OK, but there's all little glitches that drive me nuts, and I wasted so much time trying to solve these little nickel-and-dime problems. Even Photoshop hangs up a lot, which never happened on my old laptop, although that one only had 4gb RAM and 500 HDD.

Hello,
Do you have anti virus software? to run malwarebytes?
Regards:)

I have AVG. I did have Malwarebytes before, but when I had to reinstall everything, I forgot to put it back. I figured out that the problem is my flash drive, not the computer (unless the computer made the drive go bad), because now it won't work on any computer. And also, I checked the Event Log for errors, and there were none. But I don't understand why it worked for a while after I reformatted it, then went bad again. I'm not trying to move big files or anything, just a few word documents and maybe a small pic or 2.

Please furnish complete details of your problem Flash drive. Manufacturer/ capacity/ whether a genuine pen drive with manufacturer Warranty/ for how long you have been using it..

More often than not, OPs buy fake pen drives because those come at throw-away prices and then find these don't work.

If you have bought those pen drives because those were cheap , please test those with H2testW H2testw Download - Softpedia

H2testw - Download - heise online

https://www.raymond.cc/blog/test-and...-with-h2testw/

A fake flash drive is one that has been modified to display a much higher capacity than it actually has. This has become a serious problem in recent years. It is most common with larger drives (32 GB and higher) from outlets like eBay with sellers in the Orient. It has been estimated that the majority of such are fake. The packaging of many such drives is very professional and convincing. I am not saying this is your problem but it must be considered.

Flash drives are not sufficiently reliable to use as a backup media. One might think that because they have no moving parts they would be more reliable. Unfortunately that is not the case. These devices should be used primarily as a transport media with primary storage on different media.