BleepingComputer.com: Unable to Delete Files

Hello,
I had post a topic on welcome screen, but at the end i myself got the solution but this topic is more complicated.
I have to delete a file from a installer package. I used 7z to open archive and tried to delete one or more file but the file is unable to delete
a message appears "no such interface are supported".I found very difficult to delete the file i used many softwares but won't of these works at all.Please Help me.
Ashu$

Hello!

This installer package, what extension is it?

Quote

This message comes up when you used 7z to open up the archive and try to delete a file from inside it?

7zip supports many archive types. But many are supported for reading/opening only, no support for writing/creating those archives.
One example is RAR files. 7Zip can open RAR files, extract from them but it cannot create or alter them.

Hey close this topic.I had another gr8 problem i had Quick Heal Total Security 2009 installed it sowsmy pc is clean.But when i had un installed it n installed aviraantivir free it detects every file on my computer as virus.I've had also used Kaspersky TS 2009.My computer won't start n safe mode and iam also unable to acces file coz whenever i used to select file avira detect it as virus.My father also uses computer n we had very important file.We also had genuine key n a Wixp CD if we needed to install winxp again.Pls reply soon
ASHU@@@