You may have done this before, but PLEASE repeat these steps.
Please go to the Knowledge Based website:http://ancestry.custhelp.com/
And enter crash into the Keyword Search and click on Search. This will bring up a list of Knowledge Based articles based on your version of Windows. Please follow the instructions, based on your version of Windows. As you go, please make note of what you see, what you did, any error messages, so that IF that article doesn't resolve this, you can post your findings here and we can go from there.
Again, please note what you did, what you saw, or didn't see, and report them here.