Startup repair could not fix problem: Error 0x490

Original title: Startup repair could not fix problem, computer is very slow

My Dell Inspiron 1420 laptop running Vista SP 1 has been running slow for about a week, except for a day when it was back to normal. I've gone through all the spyware cleans and they haven't solved the problem. I've been getting an error message in Google Chrome that says:

"The instruction at 0x5f070f5a referenced memory at 0x5f070f5a. The memory could not be written."

And the reason I'm asking the question in this forum is because yesterday my screen went black and would not respond so I shut it down using the power button. When I started it again it automatically went into Startup Repair. At the end of Startup Repair the report said:

Repair action: System files integrity check and repair.

Result: Failed. Error Code = 0x490


It's really frustrating because tasks that used to not tax my computer now send the CPU usage to 100%. I use my computer for work so I'm wasting a lot of time waiting for it to finish things it normally does quickly. Any help would be greatly appreciated.


Question Info

Last updated March 25, 2018 Views 2,892 Applies to:

Hi Anaparastatsis,


Are you able to boot the computer successfully after performing startup repair or the computer is in non-bootable state?


If you’re able to boot the computer successfully on to the desktop in normal mode, then I try the steps mentioned below.


Method 1: Put the computer into a clean boot and then check the CPU usage

A clean boot helps in eliminating software conflicts. Visit the link below to know how to put the computer into a clean boot in Windows Vista. 

Note: Once the troubleshooting is done, do not forget to put the computer back to normal startup.


Method 2: Perform a system file checker

The System File Checker tool (SFC.exe) scans for missing or corrupted system files and repairs them.


Method 3: Delete unwanted files using disk cleanup


Method 4: Perform a memory test

Method 5: Update your operating system with the latest Service Pack


Method 6: Perform system restore

If the issue still persists beyond these steps, then I would suggest you to perform system restore.

System restore: Frequently asked questions

Additional information:


Provide event log information:What information appears in event logs? (Event Viewer)


Use Process Explorer: To determine process that is taking a lot of CPU Usage


Hope this information is helpful and let me know if this worked.

Mouneshwar R – Microsoft Support


Visit our Microsoft Answers Feedback Forum and let us know what you think

Did this solve your problem?

Sorry this didn't help.

Great! Thanks for marking this as the answer.

How satisfied are you with this reply?

Thanks for your feedback, it helps us improve the site.

How satisfied are you with this response?

Thanks for your feedback.