Hi ,Ok all understood,
I am away on holiday tomorrow for a fortnight, so hopefully one of the other techs will pick up your topic if you need further help.
Here are the thoughts that I have on this whole situation
1 You mention that certain problems started happening upon installation of SP3..... SP3 was issued 7 years ago .......
2 The 21a stop error (BSOD) is often associated with a failed installation of a service pack like SP3
3 It seems pretty clear that the malware that "knocked out your security centre" was not dealt with completely and satisfactorily and it must be remembered that malware is difficult to remove at the best of times, but by using remote assistance it is made even more difficult and often multiple reboots may be necessary thus losing the remote connection each time.....( some files often need a reboot to remove them completely and if this was not undertaken correctly, may be contributing to your problems.
4 You are trying to fix an operating system ( Windows XP) that is no longer supported by Microsoft (since 8th April 2014) and which is likely to become increasing vulnerable to infection and attack and is unsafe to use on the Internet (without taking extraordinary precautions)
5 There may be hardware errors on your computer (presumably its quite old?) as well as operating system errors and possibly other software errors.
6 Here's, some suggestions of possible next steps for your consideration.
7 Carry out hardware checks to see if anything obvious is wrong (check your hard drive by downloading the hard drive manufacturers drive testing/repair utility..) see here: http://pcsupport.abo...p/tophddiag.htm
8 If your hard drive is Ok then download a live distro of linux ( linux Puppy is good) boot from it and test your machine by using it to open documents view pictures, browse the Internet etc.... give it a good workout, if its Ok with no problems then you have eliminated most hardware issues....Puppy will be quite happy running entirely within RAM and will not write anything to your hard drive ( unless you ask it to) Linux Puppy available here: http://puppylinux.or...ing Started.htm
9 Run the Windows 7 update adviser tool..... as a wise move might be to replace your Windows XP with something more robust and less vulnerable to attack/infection/explotation. ( see here for more information) http://www.microsoft...ails.aspx?id=20
10 If your machine is too old to run properly on an updated Windows operating system then you could install a Linux or other free operating system. An alternative would be to acquire a new computer with a supported operating system.
11 If you are determined to stick with windows XP come what may, then a full format and reinstall of Win XP, and install of SP3 and all available updates together with a good anti virus, anti spyware, anti exploit protection together with a good third party firewall (or at least the native Windows firewall operational) and always operating from behind a hardware firewall (such as is found in most routers) may provide an element of protection..... BUT your whole system will still become more vulnerable to attack as time goes on...
12 once you have a fresh install of Windows, with all applications installed, all appropriate protections in place, fully updated, all junk files removed, defragged and running fast and sweet then take a disc image, verify it, make bootable media able to access the image and keep at least one extra copy safe offsite on removable media..... then in the event of software or operating system trouble striking in the future, you will be able to reimage your computer and have it back and up and running again in less time than it takes to walk the dog!
Details available from here: http://www.thefreeco...pandimage.shtml
If you have important stuff on your computer that may not have been included in your back ups ( stuff you don't want to lose permanently) then it would be wise to back it all up again and make sure you have multiple copies kept in different locations( Obviously not on your computer's main hard drive!)