You can use another computer to manually download SAS definitions from here
, save to a usb stick and transfer them to the problem pc.
The symptoms you describe could be malware related or they could be due to hardware or overheating problems caused by a failed processor fan, bad memory (RAM), failing power supply, underpowered power supply, CPU overheating, motherboard, video card, faulty drivers, BIOS and firmware problems, dirty hardware, etc. If the computer is overheating, it usually begins to restart on a more regular basis.
However, some rootkits can also trigger BSODs, shutdowns and error messages so download and scan with AVG Anti-Rootkit
If your not finding any malware then its sounds like the latter problem. When was the last time you cleaned the inside of your computer?
Dust restricts the airflow and prevents proper cooling. This in turn can cause overheating and faulty processor fans which can result in unexpected shutdowns, random restarts, booting problems, etc.
- Open your machine, check all the connections and make sure the fans are all operational.
- Check the heat sink on the processor to ensure it is not blocked with dust or debris.
- Remove the CPU's cooling unit and clean the fins on the heat sink that sits under the CPU with a can of compressed air.
- Inspect the thermal compound between the CPU and heatsink as it can break down over time so.
- Remove the cards and RAM modules, clean the contacts and reseat them.
- Feel the CPU heatsink when it powers down. It should be warm to very warm but not hot.
- Monitor the temperature of your CPU, motherboard, hard disks, voltages, and fan speeds.
See "Cleaning the Interior of your PC
" and "General Cleaning Tricks & Tips
Some video cards run so hot that they have their own cooling system. If the fan fails, the video processor will not be far behind and your system may start crashing. If that is the case see "Illustrated How to Replace an AGP Video Card
" and "10 things to know before buying a video card
In Windows XP, the default setting is for the computer to reboot automatically
when a fatal error or crash occurs. You should be able to see the error by looking in the Event Log
. Read "How To Use the Event Viewer Applet
". You can then gather more information doing a search of the Event ID number at:
"MonitorWare EventID Database
"Top 50 Viewed Events
"Windows Security Log Events
"Events and Errors Message Center
An alternative is to turn off the automatic reboot
feature so you can actually see the error code/STOP Message when it happens - this is also known as the Blue Screen Of Death (BSOD).
To change the recovery settings and Disable Automatic Rebooting
, go to Start > Run and type: sysdm.cpl
Click Ok or just press WINKEY + Pause/Break
keys to bring up System Properties.
- Go to the Advanced tab and under "Startup and Recovery", click on the "Settings" button and go to "System failure".
- Make sure "Write an event to the system log" is checked and that "Automatically restart" is UNchecked.
- Click "OK" and reboot for the changes to take effect.
Doing this won't cure your problem but instead of crashing and restarting you will get a blue diagnostic screen with an error code
and other information that will allow you to better trace your problem. You can use Google to search the error code or use the links below to investigate and troubleshoot.
"Extract troubleshooting info from Windows XP BSOD error messages
"How to Find BSOD Error Messages
"Events and Errors Message Center
"Windows XP Professional Error Messages
"Troubleshooting Windows Stop Messages
Also see, XP Shutdown and Restart Troubleshooting
and Troubleshooting Windows Shutdown Problems