error -043

Hi

Since a few days, I have increasingly started receiving the message:

'The operation can’t be completed because one or more required items can’t be found. (Error code -43)'

I first got it trying to move or delete a couple of files from my Google Drive, that I had given filenames using 'forbidden' symbols (/ and : in particular). I get the problem there: renaming. However, renaming didn't solve it, and now, I get the same error message for all my files--whether on Google Drive or my harddrive.

Help please!

System info:

MacBook 13-inch, Aluminum, Late 2008,

Processor 2,4 GHz Intel Core 2 Duo,

Memory 4 GB 1067 MHz DDR3,

Graphics NVIDIA GeForce 9400M 256 MB

Software OS X 10.9 (13A603)

Thanks!