View source for Can't rename state file; The process cannot access the file because it is being used by another process. (0x20)

Something has put a lock on the client_state.xml file, so BOINC can't copy it to client_state_prev.xml and make it anew. 

This usually happens when you have an anti-virus or anti-spyware program that's allowed to actively scan the computer. The solution is to either only scan when you have BOINC suspended or to exclude the BOINC directories from the scan. Since this cannot be done in most freeware versions of AV scanners (only in paid for versions), it's best to scan only with BOINC suspended. 

{| class="wikitable" style="text-align: center;"
 ! Original writer
 ! Original FAQ
 ! Date
 |-
 | Jorden
 | [http://boincfaq.mundayweb.com/index.php?language=1&view=429 429]
 | 04-07-2008
 |-
 |}