I have compaq windows 98 I put a mouse in and it doesn't. Work keeps asking for disk window 98 that I don't have what do I do

You seem to be missing the driver for the mouse you're trying to use. That's why it keeps asking for the Win98 disk where the drivers might be located. Since Win98 is an outdated and unsupported platform, you might not be able to use the mouse you bought no matter how hard you try. The drivers for it simply won't exist in 98 if it's a new mouse. Have you considered updating to a newer version of Windows?

Thank u so much I don't know how to update to a newer version can u help with that

Are you trying to use a USB mouse?

Try using a PS/2 mouse, or a PS/2 to USB adapter, along with a USB mouse, (Female USB to male PS/2),

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To update to a newer version of Windows;

1) You need the full installation disk.

(New genuine copy.
Note* Microsoft makes one master disk. From it all GENUINE copies are made )

2) You need to find out if your computer will handle a newer Operating System, other than Windows 98. (SE?)

Post the computer manufacturer name, and Model Number.
This is on the back of a desktop computer,next to the Windows product key, or up on the side of the computer tower.

( For HP it is Product Number. This is located in the white Service Tag.
P/N = Product Number )

Regards,
joecoolvette