I have been using ArcMap 10.2 for Desktop Advanced, Student Edition since October. Everything had been working well up until a month ago. I had been using the buffer tool with no issues, but suddenly, I began receiving invalid pointer errors. I get the same error with the dissolve tool, but not with anything else, it seems. I use Firefox and have deactivated Internet Explorer. I have also tried deleting the toolbox, as has been suggested to others experiencing the same issue. Nothing has worked. I am not computer savvy, so any clear suggestions would be greatly appreciated.