antivirus download failure on XP

hi there chaps.

so my friend (oh yeah, right, your "friend"...) has put together a second PC since upgrading his primary. all the bits inside have worked in various combinations with each other previously.

we used a completely fresh XP home edition install (legit) - all fine. installed the current versions of drivers for motherboard (network and sound card are onboard) and graphics card. then tried downloading avast for the antivirus, but it failed. we removed it and tried AVG instead, this too failed. decided that antivirus was less important since we only wanted to use the box to play bf2142. this game was duly installed along with skype which both worked fine, except when the box started to blue screen. investigation seemed to point to something called DCOM (connected to CLSID in event viewer).

we decided to completely reinstall xp again, following all the steps mentioned above with the same result.

reinstalling freshly again, we decided to sort out the antivirus download issue first to make sure it wasnt some kind of virus (though how is beyond me...). so at this point we have a new xp install (with full format), tried avast, avg and elivira all of which start to install but at some point give a failure message. googling advised trying an online scan (panda / housecall), but even they seemed to need a download which also failed. as mentioned, the skype download tried previously worked fine - it only seems to be antivirus-based downloads...!

i suppose what i am asking for is help to determine a solution for the antivirus issue, and ultimately what the blue screening is about, assuming that the antivirus does not solve that problem.

i hope some of you clever chaps can help, and thanks for reading this! :)

cheers,
chou

fyi, basic specs of this cobbled together box are:
AMD 64 3000+ cpu
ABit AN8 Ultra motherboard
2GB ram
80GB maxtor HD
geforce 6600gt graphics card
generic dvd drive

Try this solution for your DCOM problem:

Grant the user permissions to start the COM component
Grant the user permissions to start the COM component. To do this, follow these steps:
1. Click Start, click Run, type regedit in the Open box, and then click OK.
2. Locate and then click the following registry subkey:
HKEY_CLASSES_ROOT\CLSID\CLSID value
Note In this subkey, "CLSID value" is a placeholder for the CLSID information that appears in the message.
3. In the right pane, double-click AppID.

The Edit String dialog box appears. Leave this dialog box open and continue to the next step.
4. Click Start, click Run, type dcomcnfg in the Open box, and then click OK.

If a Windows Security Alert message prompts you to keep blocking the Microsoft Management Console program, click to unblock the program.
5. In Component Services, double-click Component Services, double-click Computers, double-click My Computer, and then click DCOM Config.
6. In the details pane, locate the program by using the friendly name.

If the AppGUID identifier is listed instead of the friendly name, locate the program by using this identifier.
7. Right-click the program, and then click Properties.
8. Click the Security tab.
9. In the Launch and Activation Permissions area, click Customize, and then click Edit.
10. Click Add, type the user's account name, and then click OK.
11. While the user is selected, click to select the Allow check boxes for the following items:
? Local Launch
? Remote Launch
? Local Activation
? Remote Activation
12. Click OK two times.
13. Quit Registry Editor.

Hey!
Well this seems to be a weird problem. Never come across such a thing before... Well You can download everything but the problem is only when downloading anything related to antivirus. Well i think there is some sort of virus [i guess its trojan] in your computer. So Re-install XP. Don't just format drive c: but all the available partitions. Then update your Windows first then try to donwload any antivirus. But before downloading antivirus don't install any software not even winrar and/or any necessary softwares. All the best... Post back what happens...!

thanks for the swift replies chaps.

Expertz- i'll try the dcom later tonight and let you know what happens.

SmirnOFF - as to the reinstall of XP - there is only the single partition (C: ) so i guess i tried that already :s The only other software i used before the antivirus was the drivers for the motherboard and graphics card. i guess we could try downloading the avg install on the primary PC and using a CD to transfer it as that appeared to be a selfcontained .exe - the avast install is just a link back to the avast site for the current package, so to use this i would need the motherboard drivers to initialise the onboard network card...

i hope the DCOM thing works. if it doesn't i'll try the reinstall again as suggested.

many thanks again!