I have BOINC v.4.13 and have never had problems before. my computer runs on Windows 2000, SP4, NTFS file system, and ABIT motherboard. At first, the message was "Master file fetch failed", but then it began to say "Master file parse failed". After that, it says that it couldn't contact any schedulers got http://climateprediction.... Since I'm not very good with BOINC, I don't knwo whether this is an important error or not.
Does someone else know? Is there anything I can do?

Do a sort of the messages in this forum by "most recent answer first". You will see you are not the only one having this problem. This should be fixed tomorrow, and there is a workaround in one of the forum posts.