What are these *.mdmp files? Are they important? They are in the log folder so are they playing a role? OK to delete?
They are dumps for avast errors.
They are not
important themselves, you can delete them for sure.
But, you should check if these files reaper. That will show that avast! is having trouble (conflic, crash) with other application or driver in your computer.
The problem right now it the misanalyse of AntiVir. I do not remeber if it has or not an exclusion list...
Deleting that file will bring you two solutions at a price of one