Perceived wisdom says search for *.exd files in the Temp folder and delete them. For whatever reason, that did not work for me.
I resorted to taking the proverbial sledgehammer to crack this nut and simply deleted the contents of the Temp folder ... which worked on a 2007 machine and a 2010 machine. I did take the precaution of NOT permanently deleting the files and sub-folders and allowed them to go in the recycle bin, just in case.
Touch wood, no issues so far and the ActiveX controls are, well, active again.
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