Start the laptop with a clean boot and then check if the copying function works OK.
If it does then perhaps a 3rd party program may be the cause of the problem. The link above explains how to find it if it doesn't happen when using the laptop this way.
I am leaving my comfort zone of Macs here, so bear with me. Do you have any antivirus that could be scanning files and slowing down/stopping the process?
1 
Hi @brido
Start the laptop with a clean boot and then check if the copying function works OK.
If it does then perhaps a 3rd party program may be the cause of the problem. The link above explains how to find it if it doesn't happen when using the laptop this way.
由 jayeff 完成的
Sorry but it didn't still work
由 Brido 完成的
Hey Mate,
I am leaving my comfort zone of Macs here, so bear with me. Do you have any antivirus that could be scanning files and slowing down/stopping the process?
由 Falcon 16 完成的
I dont have any antivirus
由 Brido 完成的
Do you have any 'safety' applications running? Also, when this occurs next, might you be able to send me the memory dump so I can look through it?
由 Falcon 16 完成的