I wonder if the OS is too banged up. Try a fresh install.
In regard to file loss, that's what backups are for. I can use ROADKIL's UNSTOPPABLE COPIER to sync and report so I know it's all on the backups.
That's free too.
Seagate DOES NOT report performance issues with their drives. I've run into their drives that pass all their tests but still have issues in real life. The clue I've found is the 01 or 07 value in the HDD SMART values which on most PCs I can see with a SPECCY report.
If you want me to check that out, share that report using this link:
https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
I have my Windows files on a 120 GB SSD. Everything else is on a 1 TB HDD.
I noticed performance issues initially like slow boot up times, missing files, programs not opening, etc.
I ran a disk check, it said there were errors and fixed them.
Then it was starting to happen where Windows would prompt me to restart to repair the drive without me running a disk check.
I downloaded the Seagate disk checker to see if the drive was failing. It wasn't. So i decided toove important files to an external hard drive. And i did a clean install of Windows.
I was still getting prompts from Windows to restart to repair and noticing poor performance. The hard drive was 4 years old and out of warranty. So I bought a new one. I transferred important files to an external hard drive and then copied them onto the new one.
I am still getting these error messages on the new hard drive and I have lost some filea. I don't know what could be causing this. Any suggestions would be appreciated. Thank you.

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