The usual fix is a Windows reinstall, but before undertaking that, run a full system diagnostic (F12 at powerup) to rule out out a hardware failure as the cause. If you see a hardware failure (i.e, 2000-0142, etc.) you'll need to replace the faulty component before reinstalling.  
Hi all Any help from anybody and/or Dell moderators would be greatly appreciated. Having not changed anything recently on my Dell Inspiron laptop, it suddenly crashed and since then I have not been able to re-start it successfully. I turn it on, at the Dell logo it says 'Preparing automatic repair', then another Dell logo page saying 'Diagnosing PC' and then finally a blue screen saying 'Automatic Repair: your PC did not start correctly. Any ideas/suggestions on how to fix this? Many thanks
My inspiron is stuck in Automatic Repair