Can I kosher an office microwave on hol hamoed?
It has been cleaned but not koshered before holiday.
Out of luck
Anything you kosher by burning can be done on Pesach. For example an oven, grill, toaster, pizza pan etc. However a pot, pan, silverware etc that would normally be koshered by boiling water, that can’t be done on Pesach. If you want to put one of these items in an oven for half hour on the highest degree, that would make it kosher, but may destroy it. Depends on its makeup