Running out of disk space when writing the state file will cause it to be corrupt.
(Unix only) It's also possible to get a corrupt state file if you open two instances of SlickEdit and file locking is either turned off or not working. This is almost guaranteed to happen if file locking isn't working and you run two instances of SlickEdit. You can use a "-st 0" invocation option if file locking isn't working for you. You can test this by running two instances of SlickEdit and trying to write the state file out with the "write-state" command. In the future, we may default to "-st 0". This preloads the entire state file into memory.