When the Fast 4 pit crashes on startup, with an "EAccessViolation" as the reason, often this means that the "passings" file is broken, and the software can't read it anymore.
Fast 4 stores all the information about karts passing the loop in this file. When there is a hardware error during that the computer is writing to this file, the file becomes unreadable.
In this case, we have to rename it, so the software can start a new file. No timing information of previous races is lost, because those results are stored in the database. Watch the tutorial video to see how to rename the file. Tutorial
The file is usually located in C:\Fast\PIT\PASSINGS\ ... and then the date of today, like "20141115.sms"
It does mean however, that your hard drive is probably going to crash soon. Hardware errors like these are not normal, and the hard drive should be replaced as soon as possible by a skilled technician. Be sure to contact us before you replace it, because we have to take a backup of your database and disconnect the computer from our webservers.