Whenever the Mac OS X behaves abnormally then there might be Mac error log. In Macintosh there are various log files which have useful information sent by numerous system applications and processes. But sometimes due to some unknown causes there would be unpleasant circumstance appears which affects your system performance adversely. One of similar condition come across when Mac error log. Due to this you may experience frozen cursor on the screen, Mac error message and unexpected restart of system etc. So you need to diagnose this problem and for this go to Applications >utilities. After that you would get /Library/Logs by which you can find Mac error log. If there is suspected plist files then move them to desktop. Now restart the system.
Thus problem regarding system can be resolved after doing so. In case of file losing case you should check for duplicate copy of data which ever backed up earlier. But if you haven't created such backup earlier then it is beneficial to go with Mac Data Recovery Software. This is the widely used way for regaining every type of lost Mac file without problem. It recovers damaged or inaccessible file in quickest manner. Hope you understand about how to resolve Mac error log now.