That's not something you can change in System Restore. It's in the BIOS, and it's shown long before the machine even knows there's something like Windows going to run ten seconds later.
The usual remedies are:
- At boot, go into the BIOS setup screen (that's something like pressing del or escape or F2 or another key or key combination, depending on the motherboard, mostly it's shown on the screen) and find out how to reset it back to defaults. While there, check the date and time also.
- Replace the battery on the motherboard.
But it's possible it points to a more serious hardware error.
Hope this helps.
I keep getting error messages when I start my computer. error 0271 check date&time. error 0251 System CMOS check sum bad. I tried two system restores but it failed. can anyone help me? I have an emachine model T 2542 year 2002 windows xp.