To diagnose a problem in Windows XP, start the operating system, access the Device Manager dialog box, and check whether it reports conflicts between components or individual errors. If the operating system fails to boot up, start it in Safe Mode via the Windows Advanced Options Menu. Finally, check if your computer is infected by running a scan with an anti-malware program. If all options fail to ascertain the problem, perform a complete system restoration via the System Restore function.
To access the Device Manager dialog box, click Start, click on Control Panel, and click on the Hardware and Sound link. Find the Devices and Printers section, and click on the Device Manager link. Once the dialog box appears, double-click on each component, open the General tab, and check the Device Status screen. If the selected device is causing problems, an error code should appear in this section.
To start the operating system in Safe Mode, restart the computer, and keep pressing F8 while Windows XP is booting up. After accessing the Windows Advanced Options Menu, select the Safe Mode option, and press Enter. Once Windows XP loads, download and install an anti-malware program, such as Malwarebytes, and run a scan to diagnose malware- and virus-related problems. As a last resort, use the System Restore function by accessing it from the System Tools folder in the Start menu and selecting a point in time before the problem first occurred.