File opening very often very slow

[TechnoMax]

I have a decent PC with an i7-6700 CPU, 16 GB RAM and several SSDs and several NAS storage devices connected with Gigabit. My Windows is 10 Pro 1809 Build 17763.379.
But very often, the opening of a file takes endless time, typically some 20 to 30 seconds. At first I thought it is a slow NAS and replaced it. But this did not help.
Now I tested several small text files in txt, rft and doc format on a local SSD folder. I changed the apps to other apps (Textmaker instead of MS Word for instance) but it did not help. Sometimes a file loads instantly when I load it a second time. But sometimes not. Of course this is not text specific, JPGs or MP3s behave the same.

What can I do to speed up file opening again?

 

[Golfdriver97]

Perhaps disconnecting the NAS? Trying without that involved?

 

[TechnoMax]

No, the NAS has nothing to do with my problems:
I started Windows from an external SSD and had no lags anymore, neither with the internal SSD folders nor with the NAS. I got the same speedy results when I booted my main PC again but now from a new user account.
Somehow I have to "clean" my user account, but how?

 

[Golfdriver97]

Maybe by reloading windows? I mean as one of the reset options?

 

[heyanil673]

Take a deep virus search on your PC because sometimes when we use the internet and forget to turn on the defender on that time while that time a lot of sites sends virus to your system and because your defender is not working on that time so it won't help you and after some time powerful pc gets slow. If this really happened to you then you will have to reinstall your windows.

 

[TechnoMax]

I used several antivirus apps (booting from an external Windows SSD), that could not find anything.
I capitulated and wiped the disk and reinstalled everything anew. Unfortunately I was too quick and I nearly lost important files: I mounted a backup as a virtual drive but my user login files were protected from me (!). I swapped the boot SSD and restored my latest backup, but this could not boot, probably because of bootmanager problems that I could not solve.
Text time I will better take another disk2vhd image before I wipe the boot partition, these I always could "boot" so far. in VMWare Player.

 

[Gayle Lynn]

And you run chkdsk and sfc?