What version of windows? This might be caused by using a version of Lightroom that is too old for the version of Windows you are using.
Lightroom4, Windows 8
Lightroom 4 should be supported on windows 8. You might have good luck by making sure you have updated it to the last version of LR 4 that was released:
Make sure you get the correct version of your version of windows (64 or 32 bit)
I downloaded latest version. No change.
My only other guess would be a permissions problem on the destination where you are trying to move your files to.
Permissions problem? Please say more.
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