Question What causes very slow copy/paste transfer?

[TheFlash1300]

Hello. In the past (around 10 months ago) my laptop had a very good copy/paste transfer speed, it was around 150-200MB/s. Now, the speed is mostly around 10-20KB/s, rarely jumps to around 8-10MB/s for a short period of time, several seconds, and then gets back to 10-20KB/s.

The health of my SSD is at 97%, according to CrystalDisk. The OS is Windows 10. The transfer speed from the laptop to USB is even slower.

What causes this problem? Can someone help me?

 

[SkyNetRising]

We know nothing about your hardware. Please list specs of your system. What storage devices are you using?
What are source and destination for copy/paste operation?

Generally with SSDs - performance drops significantly, if SSD is full.
It needs some percentage of space free for drive maintenance and wear leveling to work properly.