From my knowledge this error appears to prevent errors with Windows and hardware related software that is installed. Mostly its indication that the software or driver or one of the files is not signed for the version of Windows you are using… in your case Win XP.
The Windows system perform signature detection whenever an INF file is used to install hardware from a designated device class. You can simply Continue Anyway button to complete the installation of the software
For the future you can disable such kind of message.
1. Open System in Control Panel.
2. On the Hardware tab, click Driver Signing.
3. Under File Signature Verification, click Ignore, Warn or Block
Click Ignore to allow all device drivers to be installed on this computer, regardless of whether they have a digital signature.