hello. I have a problem that when i switch on my computer it dosn't pick up windows, it gives me a message to press alt, ctrl and del to restart.
i am sure that i isn't a problem of hard disc because it is new.
so can you tell me how can i fix it?
You need to boot to your OS installation disk and do a repair.
If you had used a hard drive from a different chipset Pc to this one, then there will be a cvompatiblity problem, you'd need to do a re-install.
Another thing it might refer to is that the first boot priority must be the hdd and not any other device, this is particularly a problem with Dell computers (it's a safety feature, supposedly) so if you have just installed Windows to the hdd, you need to change the boot priority from the cd/dvd drive (or whatever) to the primary hdd, however, you would have received a mesage like "No hard drive found") when the first boot device is not the OS hdd
Sometimes, though, it could refer to a ram issue like mixed ram values or a faulty ram chip . AND/OR it might also be a BIOS configuration error like the invalid use of RAID or AHCI handling.
Give more details to your issue like your PC specs (PSU, GPU, ram, type of hdd), what OS, motherboard model number ... and whether you installed the OS using a CD/DVD data installation disk or a usb memory stick.
It might seem like there should be a simple answer to a simple question but there are no simple solutions with computers.