Mountain Lion crashing while copying and pasting

I'm trying to drag a lot of files from an external drive to my hard drive and it crashes a lot. Anyone experiencing this? I have a new Mac Mini that I transferred a lot of files over to from my iMac through the Migration Assistant.

What drive? How is it formatted? What kind of connection? Define "a lot".

At the least, you should make sure Mountain Lion is fully updated. Also download Onyx and run its full suite of maintenance and cleaning tools. You may also want to investigate that external drive further... it may be failing.

Thanks for the reply. I think I figured something out. Might be useful for others. Between Dropbox, Google Drive and Teamviewer they were causing this sort of half-freeze restart of Finder or SOMETHING weird. When I stopped all those it seemed to allow me to transfer large batches of data without crashing. I also had just bought a Mac Mini and used the Migration Assistant to transfer a lot of applications and settings and data from my old iMac to the new Mac Mini, and it may have contributed to the weirdness. The two computers seemed to be confusing those services because they had the same name or something. I'm medium savvy level but I think something in that mess was causing this problem. Thanks!