Description:
If Plex crashes when you try to open it, there maybe some corruption in your Plex.ini file.
Solution:
Replace the toolbar info sections at the end of the Plex.ini with the corresponding entries from a valid (working) Plex.ini from another PC or try deleting the toolbar info sections from the end of the Plex.ini; for example:
[Control Bar State Info-Bar36] which is at the end of Plex.ini