How do I reopen LibreOffice when it has 'Unexpectedly quit"?

Trying to use LibreOffice and a box appears saying

The last time you opened Libre Office,
it unexpectedly quite while reopening
windows. Do you want to try and
repoen its windows again?

It won’t reopen. What do I do?

Maybe your user profile got corrupted. Try resetting it as explained in: https://wiki.documentfoundation.org/UserProfile . Be sure to not delete the old profile before you have restored your templates and your macros (if any).