Jukebox using XP OS left standing long time won't boot

[Polly Grigora]

Needs XP to run the Jukebox software

Uses laptop motherboard

Not booted it in the last 2 years

Now fails at boot, forget exactly what the screen shows but do remember some error reported

Took it for granted that the small battery for the BIOS clock etc has gone flat (there is no battery fitted to power the motherboard)

Is there an easy fix for this problem if it is due to flat battery?

Is it as simple as plugging the mains adapter in to charge the battery and later set the Bios clock?

Or am I getting it all wrong and the OS will also be broken?

Thank you in advance

[Polly Grigora]

Problem was solved by leaving switched on for a while and then rebooting to enter BIOS, set a time in BIOS and rebooted, lives to play another day