Update: Here's a copy of a list of programs that I use to defend PCs against viruses and fix them after they've been infected.
On 2002-06-19, I uninstalled my copy of Norton AntiVirus 2002 from my laptop running Windows 2000 Professional. I was subsequently unable to use networking. Here's a list of the symptons and how I fixed the problem.
I uninstalled Norton AntiVirus 2002 because I became annoyed with their pop-up windows demanding that I renew my subscription. I don't have much patience for software that turns my desktop into a vending machine. In its place, I installed free antivirus software AntiVir XP. After the uninstall, I couldn't connect to the Internet.
When I can't connect to the network, I use "ipconfig" (Start->Command Prompt, and type "ipconfig") to check the status of PC's newtork. Ipconfig showed that I had no IP address assigned to my computer. I used "ipconfig /renew" to try and get an IP address — but this failed, with an error message asking me to make certain the cables were correctly connected, or perhaps that I had an "internal error" of some sort.
Skipping a lot of intermediate steps and about three hours of fooling around, I will just summarize all the error indications that I found. The desktop's "My Computer" icon, when left-clicked, has a menu item "Manage." The "Manage" program brings up a window, and in the left-hand side of that window you can choose various managment functions.
This latter message was a source of wonderment, because the DHCP service itself showed no dependencies. An excursion through the registry showed nothing of the sort either.
A Google search turned up a review on Amazon.com of Norton SystemWorks 2002; the reviewer commented that Norton's uninstaller would fail to break the dependency of DHCP on Norton's SYMTDI. This was the vital clue (thank you, whoever you are). A search on Norton's web site revealed nothing about DHCP, but Norton does confess that NetBT is sometimes afflicted with a similar problem. Norton does let you download a cleansing program, and then recommends you clean up your registry.
I cleaned up the registy by deleting references to two non-existent Norton programs (SYMTDI and SYMREDRV). However, DHCP still would not start (Manage->Services->DHCP Service, first tab, "Start").
To fix this, I decided to reinstall DHCP. On a real computer (Macintosh, Linux) this would consist of either re-downloading or deleting a simple Preferences file; on a PC, reinstalling DHCP is a bit of mystery.
To reinstall, I went to Start -> Settings -> Network and Dial-Up Connections. One item is called Local Connections. The Properties of this item reveals a "General" tab. There's a list of "Components checked are used by this connection," which included DHCP. After writing them all down, I unintsalled all the components. I rebooted the computer for good luck (which complained about networking problems) and then reinstalled all the components I'd deleted (using the "Install" button).
DHCP was back up immediately after reinstalling — no reboot needed.
I was informed — via email from readers of this page — that fix in the previous paragraph for Windows 2000 does NOT work for Windows XP because Windows XP does not allow you to uninstall TCP/IP. "The Microsoft Knowledge Base Article Q299357 about refreshing TCP/IP registry keys does not solve the issue either."
I've received several emails, all with essentially the same fix for Windows XP. Here's the first fix I received, from Chuck Simciak:
In WindowsXP (and 2000 I suppose) you can remove DHCP's dependence on Norton Anti-Virus by doing this:
DHCP should work again.
Should a problem come up (messing up the registry entries) you can also press F8 (or is it F5?) and select Use Last Known Good Configuration from the boot menu. That will restore various registry entries to what was used last.
I'm not sure why Norton installs this key. For some types of firewall software a dependency like this is added to ensure the firewall is running before DHCP grabs an address. Of course, Norton Anti-Virus should have removed this dependency when it was unistalled. Clearly its a bug in the uninstall routine.
Kerill Titiyevskiy of MIT found a similar solution, and a URL to the official Norton fix although the fix doesn't officially cite the "uninstall" problem. To quote the web site:
To edit the registry:
I have not seen any reports that indicate that NISDRV is a problem, but I expect that it couldn't hurt to delete them as per NAV's web site instructions.
Update, 2002-09-18: Several people, including help desk managers, have written to say that they've tried the "Edit Registry" fix for Windows XP and that it works just fine. My thanks to everyone who's written to suggest fixes and confirm that they work.
This page is really in the wrong place for historical reasons; it should be on my professional web site, where I've got my professional contact information as well as some interesting speech technology software. And I've got a list of programs I use to defend a PC against intrusion and/or fix them after they've become infected.
And I've written a book about how to create, understand, and apply revolutionary innovations in business and technology.
BACK to the Quddities page.