I receive lately the error message "the instruction at "0x00000000" referenced memory at "0x00000000" could not be "written".
However Microsupport announces:
There are no documents that match your search for "the instruction at "0x00000000" referenced memory at "0x00000000" could not be "written"
and at certain stage it proposed to install SP3 to correct this.
but when i try to install the service pack 3 I receive a message:
"internal error"
What cen be done?
Please advise
Thanks

Does this happen at bootup, or is it a result of running an application/program?

It could be a Virtual Memory type error, OR, the application (or some files supporting it) may be corrupted.

1. Is Windows managing your virtual memory, or have you tinkered with it?
   
2. How much free space is on your drive?

Based upon the above, the following may or may not assist in problem resolution, but it's a good starting point.

Have you "cleaned" junk from your machine lately? A good (free) "cleaner" for removing junk from your system is CCleaner. It also performs a "clean-up" pass on the registry.

CCleaner - Download
(Click on Download from FileHippo......, in the PayPal box)

Alternate Download;
|MG| CCleaner Slim (No Toolbar) 2.15.815


Once you download and install it, open the program then click on (left hand side) OPTIONS, then COOKIES. Any cookies you want to save (trusted sites, places you have usernames/passwords), highlight them in the left column, then (using the directional arrows between the panes), move them to the right hand column under "Cookies to keep".

Still under Options, click on Advanced. Remove the check mark from the box for "Only delete files in Windows Temp folders older than 48 hours".

Leave all other settings at the default.

Then click on Cleaner (on the top left). When that window opens, click on Run Cleaner (bottom right of the window.)

When it finishes, close CCleaner, and restart your machine. (Some files will not be deleted until a restart is performed. (I do not advocate running CCleaner on each boot. I run it once or twice a week.))


Once junk is cleaned up, perform a defrag on the O/S drive. Here are some good freeware defrag programs;

Auslogics - Download Auslogics Disk Defrag
(Uninstall any previous versions before installing the latest version.)

Defragment Disk | Smart Defrag | Free Disk Defragmenter Download

|MG| Diskeeper Lite 7.0 Build 418

JkDefrag v3.36


Installing SP3;
Steps to take before you install Windows XP Service Pack 3

Please answer the above questions.

Thanks Dan
.
It appears irregularly when surfing or working on any applications.
For instance it appeared twice now just when I tried to read a query to this error which lies under your answer.
I use the CCleaner daily, after work, and I defragmented the C partition some days ago.
Do you have any other thoughts?

It appears irregularly when surfing or working on any applications.

This indicates it's probably a process or service which is running.

Have you added any new software recently?

What do you run for an A-V and Firewall?

Are any other security elements running? (SpyBot-S&D, Ad-Aware, etc.)

no, no new programs added
yesterday scanned with Malwarebytes - no malicious items found
for AV runs Eset NOD32