It depends on which backdoor trojan is on your computer. There are some that are not easily removed. If you do any banking or other financial transactions on the PC or if it should contain any other sensitive information, please get to a known clean computer and change all passwords where applicable. If the trojan is easily removed, keep an eye on any bank/credit card statements. Otherwise, it would be wise to contact those same financial institutions to apprise them of your situation.
As to the Symantec instructions, I do not agree with the recommendation that you disable System Restore. Clean the computer first, then create a fresh restore point and use Disk Cleanup to remove all but the last restore point.
If you have an anti-malware software installed, I suggest updating and scanning with that as well. Follow that up with an on-line scan.
Let us know if you need additional assistance.
Edit: Since you posted while I was composing, before scanning with another software, etc., I suggest you clear Temp Files. A simple program for that is ATF cleaner. The instructions are simple:
Download ATF Cleaner by Atribune from http://www.atribune.org/index.php?op...d=25&Itemid=25
. Save it to your Desktop.
Run ATF Cleaner
- Double-click ATF-Cleaner.exe to run the program.
- Click Select All found at the bottom of the list.
- Click the Empty Selected button.
- Click Exit on the Main menu to close the program.
- Shutdown/restart the computer.
Follow that with further scans.