Lightroom Lockout!

The other day, after receiving my free RSP/Lightroom e-mail from Adobe after an epic struggle I got Lightroom up and running and it went like a dream until this morning. While importing some pics, Lightroom crashed and a message came up "Lightroom has a problem and needs to shut down" Since then, I haven't been able to open the programme - I am simply locked out every time by the same message. I tried downloading the trial version again using my special URL but was informed that it had already been used and was not now invalid. I'm at a loss. Has anybody experienced this and if so, is there a soloution?

Thanks,

Seamus Finn

PS Finally sorted out the problem by fiddling with the shift and ctrl keys alternatively when opening Lightroom. It seems the programme was reading an external drive as a network system and behaved accordingly as I understand Lightroom cannot be networked. I only solved the problem by trial and error. Holding down the CONTROL key while clicking on the Lightroom icon to open the programme brings you into the database location and from there I was able to 'unfreeze' my problem.You can also create new databases, it seems. Hope this is of some use to others who may be similarly afflicted.

Seamus