You may need to try re-installing Microsoft Visual C++ Redistributable 2012. Only use the official Microsoft download as there are many fraudulent sites offering malicious dll fixes.
But first find it in the Windows control panel, and try a repair. (Win Control panel, Uninstall a program, uninstall or change, select change and then repair)
Thanks for your reply and suggestion - just tried it but LR still same.
Sorry that made no difference.
Are all the other tools working? Is the crash only happening when making selective black point adjustments? If so you could try reporting it on the feedback forum at Get Satisfaction. Adobe staff can then try to re-produce the error. Or first search the forum to see if it has already been reported, although I’m not personally aware of a bug.
Adobe support are aware of the problem. The issue only seemed to have started after either the LR update (end January?) or the CC app update recently.
Have googled everywhere - no luck