hey everyone, i recently lent my hard drive to a friend so he could format his mother board ( im not quite sure what he used it for but it was something like that ) and when i got it back to put in my pc it comes up with the safe mode thing and start windows normally. and i chose to start from last known good config but it just loads that grey bar and then freezes and does nothing. i took it down to my friends house and it works perfrectly fine there. can anyone help please???

Did he use it as the main boot drive?
When placing the HDD in another computer it took all of that computers configurations,for mobo and cd,dvd,video card,etc. you will have to go into the bios and let it refind all of your configurations again.With newer computers you have a better chance of it finding everything.

bean55

First off you should find out what you friend did to your HDD....also what I don't get is why did you friend need your HDD to format his motherboard?? Your friend should have the media to format his drive and a HDD to start his installation rather then needing your HDD to do that. Advise is never give your HDD to anyone besides yourself as you never know what they did or copied from your HDD would go into "Privacy" Matters. Because as mentioned by bean55 is correct it changed your HDD settings from your settings to his and most likely if getting safe mode constantly corrupted or damage a critical file your computer needed and now you will be left with a complete reinstall of your O/S to match with your motherboard and hardware....That is going to be your only option if your friend can't fix what they did to your HDD...