ach. nevermind. The logfile/traceback is misleading. It appears that somehow /home/mark/.cache/software-center/ had its ownership changed to root:root. changing it back to mark:mark (My username) solved the problem. This was a fresh install of ubuntu as of yesterday. Perhaps the default permissions are wrong? More testing is required on my end.
ach. nevermind. The logfile/traceback is misleading. It appears that somehow /home/mark/ .cache/ software- center/ had its ownership changed to root:root. changing it back to mark:mark (My username) solved the problem. This was a fresh install of ubuntu as of yesterday. Perhaps the default permissions are wrong? More testing is required on my end.