Reinstalling doesn't remove the blockchain data from my understanding so the files would remain corrupt. They are likely corrupt so you can delete it manually and wait for the resync but the better way is to do the following:
1. right click on Dash Core shortcut and add -reindex to command line
2. start it once and wait for reindex to complete
3. stop wallet and remove that -reindex addition
4. start wallet, should be no error now
https://www.dash.org/forum/threads/mingw-runtime-assertion.13445/