Wireless connection problems caused by virus??

[Nickyxx5]

My friend has a Dell Inspiron laptop running Windows XP. He has recently
found that he is unable to connect to his home wireless network. He receives
the error message that there is "limited or no connectivity", but at the same
time the signal strength is reported as good, and when he goes into the "View
Wireless Connections" window, it reports that he is connected to his wireless
network. But he is unable to connect to the internet or Skype. I don't
understand how the computer can be reporting limited connectivity and good
signal strength + connection to network simultaneously.

It is definitely not a problem with the router as other laptops in his house
are able to connect to the router and to the internet without difficulty.

In order to try and resolve the problem we performed a system restore back
to a date last week when he thought everything had been functioning normally.
This did not resolve the problem, but at this point I noticed that the
wireless network connection icon had disappeared from his taskbar (it had
definitely been there before), and that a red security centre icon was in the
taskbar, reporting that no virus protection could be detected. (I am not
certain whether or not this had been there before). He had previously been
running Windows' own virus protection, but now Windows cannot even detect its
own anti virus software.

I think the next step must be to reinstall some virus protection but I
wonder if anyone else could offer us some advice....
o Is it likely that the original wireless network connection problems could
have been caused by a virus, which has now also disabled Windows' antivirus
software?
o If so, are there any particular viruses that are likely culprits? (If we
could identify these I might be able to download removal tools on my internet
connection that he could then try).
o If it is unlikely that the networking problem was caused by a virus, what
are other likely causes and solutions?


Many thanks in advance.

 

[Lem]

My friend has a Dell Inspiron laptop running Windows XP. He has recently
found that he is unable to connect to his home wireless network. He receives
the error message that there is "limited or no connectivity", but at the same
time the signal strength is reported as good, and when he goes into the "View
Wireless Connections" window, it reports that he is connected to his wireless
network. But he is unable to connect to the internet or Skype. I don't
understand how the computer can be reporting limited connectivity and good
signal strength + connection to network simultaneously.

It is definitely not a problem with the router as other laptops in his house
are able to connect to the router and to the internet without difficulty.

In order to try and resolve the problem we performed a system restore back
to a date last week when he thought everything had been functioning normally.
This did not resolve the problem, but at this point I noticed that the
wireless network connection icon had disappeared from his taskbar (it had
definitely been there before), and that a red security centre icon was in the
taskbar, reporting that no virus protection could be detected. (I am not
certain whether or not this had been there before). He had previously been
running Windows' own virus protection, but now Windows cannot even detect its
own anti virus software.

I think the next step must be to reinstall some virus protection but I
wonder if anyone else could offer us some advice....
o Is it likely that the original wireless network connection problems could
have been caused by a virus, which has now also disabled Windows' antivirus
software?
o If so, are there any particular viruses that are likely culprits? (If we
could identify these I might be able to download removal tools on my internet
connection that he could then try).
o If it is unlikely that the networking problem was caused by a virus, what
are other likely causes and solutions?


Many thanks in advance.

Windows XP messages concerning wireless "signal strength" or that a
wireless network is "connected" can be misleading. A common reason for
the "limited or no connection" message despite good signal strength is
that connectivity is being blocked by some security feature: a network
encryption password mistyped; wrong MAC address; or other restriction
set in the router.

One way to test things is to connect the computer to the router using an
Ethernet cable. This bypasses all wireless security, and if it works,
the next step is to either double-check all wireless security settings
on the computer or disable all wireless security settings on the router
and see if you can then connect wirelessly.

OTOH, there definitely are viruses and other malware that disable
antivirus application. When you say you have "Windows' own virus
protection" do you mean Windows Live OneCare? I haven't heard very many
good things about that. What do you have for checking for non-virus
malware (e.g., Spybot Search & Destroy, Ad-Aware)?

Here is some good, although generalized, malware removing advice from
MS-MVP Malke:
http://www.elephantboycomputers.com/page2.html#Removing_Malware

At the very least, go to the website of one or more of the reputable a/v
mfrs who offers a free on-line scan, and do it:

http://housecall.trendmicro.com/
http://www.kaspersky.com/virusscanner
http://security.symantec.com/sscv6/default.asp?langid=ie&venid=sym
http://onlinescan.avast.com/
http://www.eset.com/onlinescan/

--
Lem -- MS-MVP - Networking

To the moon and back with 2K words of RAM and 36K words of ROM.
http://en.wikipedia.org/wiki/Apollo_Guidance_Computer
http://history.nasa.gov/afj/compessay.htm

 

[Nickyxx5]

Thank you so much - that was very helpful.

I was just quoting my friend when he said he had "Windows own" anti virus -
I think he meant that he was just relying on the Windows defaults, which
probably means he had not installed any specific antivirus software, so this
could well be the root of the problem. I have already downloaded AVG,
AdAware and Spybot S&D for him to run - I will check out the websites you
recommended too. If fixing any virus issues doesn't help things, we will try
connecting with the ethernet cable as you suggested.

 

[smlunatick]

Thank you so much - that was very helpful.

I was just quoting my friend when he said he had "Windows own" anti virus -
I think he meant that he was just relying on the Windows defaults, which
probably means he had not installed any specific antivirus software, so this
could well be the root of the problem. I have already downloaded AVG,
AdAware and Spybot S&D for him to run - I will check out the websites you
recommended too. If fixing any virus issues doesn't help things, we will try
connecting with the ethernet cable as you suggested.
--
Nickyxx5











- Show quoted text -

Your friend may be confusing Windows Defender as an anti-virus
system. XP never had any anti-virus built-in and Windows Defender
does only spywares (at a minimum at best.)