Unexpected Application Error

I've not been able to start Rekordbox for the last week or so -- every time it states "Unexpected Application Error".   My system is up to date - has switchable graphics, both Intel & Nvidia (both on current drivers).  Rekordbox crashes whichever mode I run it as.

I've tried uninstalling, reinstalling... 32 bit, 64 bit.  Unable to get the application to start.

Please provide with a fix, I need Rekordbox urgently.