Try booting in Safe Mode and use system restore to when it worked. Then get rid of viruses and other parasites.
If you cannot start in safe mode, then at the boot menu choose "last good configuration.."
I was browsing through websites a couple of days ago and it was crashing really bad so I switched the laptop off by the mains then was going to restart it. However when you switch it back on, you know it loads before going on to the main blue screen for you to log on, well it didn't go there, it kept constantly loading & loading and never done anything else, I've tried fixing it but there's nothing I can do, can anyone help me please??

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