Windows 7 Suddenly copying to either win7 HD is ten times slower

[pzbrawl]

A win7 box has two drives, 500GB and 2TB. Each is about half full. Neither reports problems.

Suddenly, as of a few days ago, copying files to either drive from another 'puter on the LAN is ten times slower than it had been, but copying files between the two drives on the box is instantaneous.

What should I look for?

 

[Neemobeer]

How are the computers connected to the network? Wired or wireless?

 

[pzbrawl]

Wired.

 

[Neemobeer]

I would look at speed and duplex settings. If there is a problem they can drop down. The drop will be in increments of powers of 10.