Hello,

I have about 1,8 Tb of data. I was using two external HDDs for a main use and copy and MicroSD cards as third copy. Let's call them Copy1 (main HDD copy), Copy2 (second HDD copy) and Copy3 (copy on MicroSD). These HDDs were old - about 11 years old. I was using FreeFileSync program to copy files from one disk to another. About 3 months ago I noticed that some files on Copy1 were corrupted - the photos had some parts covered by colorful lines. The same with videos - sometimes it was jumping forward, sometimes colorful distortion appeared. It lasted only few seconds and it was in about 500 files from these 1,8 Tb (I knew that it was in about 500 files because I checked it by FreeFileSync by comparing checksums between both copies). These files were fortunately fine on Copy2. So I decided that it's time to replace this disk. I've bought internal HDD and mounted it inside my PC. Let's call it Copy1A. I copied all the files from Copy 2 to Copy1A. It seems to work fine. I threw away old Copy1. Unfortunately, about a month ago I decided to compare my new Copy1A with the second, old Copy2. And about 20 files were corrupted. It was weird, because I was copying files from this Copy2 to new Copy1A and all of them seemed fine, so why few days later some files in Copy2 were corrupted? Anyway, I copied it again - this time from Copy1A to Copy2. Everything seemed fine. Today I added some new files and compared it again - and about 8 files were corrupted. One of the corrupted files was copied today! How could it get corrupted? I'm starting to think that FreeFileSync corrupts files during copying them. I replaced the corrupted files with correct ones and compared discs again - now it seems that both copies are 100% good. I also checked Copy3 (MicroSD cards) and it's also fine. I will wait for about a month and will compare Copy1A and Copy2 again. But I think that it's also time to replace Copy2, it's also old - about 11 years old. This Copy2 was not very used, it was lying in the shelf all the time and I was connecting it only sometimes to add new files. My question is - do you know better method to check the integrity of the files? Currently I can only compare checksums between two disks and I get the info that some of them are corrupted. But by this method I don't know whether these files are corrupted on Copy1A or on Copy2? I can only see that these files is different on both discs, but on which one is it corrupted? I can only guess that it's corrupted on Copy2, because it's a lot older. If this is a photo which is corrupted I can easily open it on both discs and check on which one it has distortions, but if it's for example a long video, in which only few seconds are corrupted, I won't watch it second by second on both discs to check on which one it is broken. It is scary, because the disk seems to work fine, you want to open some old photos and suddenly they look like this:

https://forum.benchmark.pl/uploads/monthly_2026_02/image.png.b4694a3d1936e624eeb11d81d3284255.png

And there is not any warning that something is wrong.

I was thinking about buying a cloud as a copy, but will I be able to compare checksums between the cloud and HDD copy?

I think that it would be the best to create a checksum of Copy1A and to write it on another disk. Then I would be able to compare this checksum with the copy and I would know if the files are corrupted. Because what is the point of comparing checksum between two discs if I don't know which of them is broken? Is it possible to do it this way - to compare checksum written in the text file with the copy?

I am using Windows 11.

I don't know why everybody say how extremely bad and unplayable is original Game Gear screen. You can see on this comparison that the original screen blends pixels just like CRT TV. On modern screen you can see all square pixels clearly which looks bad in my opinion, but on the original it's really great. I don't know how did they do this - it's LCD, but it looks like mini CRT. It's perfectly playable for me. Maybe I was just lucky to have the screen in great condition - I know that many of them are damaged and can't be repaired. But if you have the screen like this I don't understand how would you prefer modern screen :D And I have the oldest, first japanese version. My Game Gear has some issues, but the screen is absolutely perfect.

https://youtube.com/shorts/VcDkQOzhxvc?is=OR7zn9VUPL1vcBrg