Can't Copy Files from PC ? topic

Never seen this before .... I plug phone into usb on PC I can see the phone open folders but when I try to copy a file to the phone I get an error message that device has stopped responding or has been disconnected. Running Liquid 3.0 and have had no problem moving files before this on this ROM. I even restored to an earlier version of the ROM with same results. Have tried different cables and USB ports to no avail. Any ideas?

Edit: hmmm ... something has change on my desktop. just tried on wife's computer (both running Win7 HP) and copied a file no problem. I can delete something off of phone but can't paste ...