On starting my pc black screen is coming and shows Enter password. I don't know what it is asking for. please help I am unable to start my computer.
Do you mean something like this:
If so it needs your BIOS password, which you should already know if you have configured the PC to require it upon booting. Or is this a secondhand one you've bought and cannot get past this screen?
If the latter then you can reset the thing by opening the computer up and removing the CMOS battery (tons of help online - search Google for it, there will even be YouTube videos if you need them) for ten minutes before putting it back and starting again.
If it is a laptop, you may have to remove the battery and short out a couple of contacts on the motherboard. Check with the Samsung web site's support pages for this system.
I have tried many times... I removed battery for several times.. 10mins,20 mins, 30 mins.. N today I changed the battery I bought a new battery but still enter password is coming... Wht to do now.....
Some models have us call in to reset that password if methods you find on the web don't work.
Be ready to prove it's yours since when the maker does this it's a form of theft protection. The makers sometimes get flamed over this but hey, if it's yours legitimately, it's like you locked your keys in your car and pay a little to the locksmith.
It must be worth it to get this done, right?
you need a professional to solve this issue and you can find him at daniweb good luck to all