This is by far the most maddening problem I've ever had, and to be honest I don't even know how to say what the problem is. Here goes:

I'm having severe problems with my wireless connection. I'm running a custom desktop with a PCI wireless card connected to my home router. So far my computer is the only one having this problem, so it isn't the router.

The gist of what's wrong is, sometimes I'll be connected just fine and go at full speed. The connection will then suddenly go half-dead; the taskbar indicator says it's still fully connected, but any attempts to browse the internet are either abysmally slow or time out altogether.

Over time, every attempt at fixing this that I have tried (disconnect/reconnect, reset router, DNS flush + IP renew) has been met with every result imaginable. The truly vexing part is that there's apparently no pattern whatsoever to what works and what doesn't. For example, disconnect/reconnecting will sometimes work, then it will work off and on, then it will not work at all, then it will usually work but sometimes freeze, etc.

I'm frankly getting quite angry because I simply don't even know where to start. Every time I think I've found a consistent behavior I can work with, it goes and does something completely different. If anyone has any clue where to start with this, or even just an idea of how to investigate the source of the problem, I'd greatly appreciate it.

If you haven't yet tried to repair the connection, go ahead and do that:
Right click on network connection and click Repair.
(details of what it does here)

Then I would scan for malware. If you don't have any scanner installed, try these online ones:

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TrendMicro™ HouseCall Java Scan

• Please go HERE to run the Trend Micro™ HouseCall Scan.
• Click Scan now. It's free!
• Read and put a Check next to Yes I accept the terms of use.
• Click the Launching HouseCall>> button.
• If confirmed that HouseCall can run on your system, under Using Java-based HouseCall kernel click the Starting HouseCall>> button.
• You may receive a Security Warning about the TrendMicro Java applet, click YES.
• Under Scan complete computer for malware, grayware, and vulnerabilities click the Next>> button.
• Please be patient while it installs, updates, and scans your system.
• Once the scan is complete, it will take you to the summary page.
• Under Cleanup options, choose clean all detected infections automatically.
• Click the Clean now>> button.
• If anything was found you may be prompted to run the scan again, you can just close the browser window.

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Also, here is another scan you can try:
http://onecare.live.com/site/en-us/center/howsafe.htm (requires IE; also works with most Windows systems but is only in Beta with Vista)


Then I would test connectivity by temporarily disabling firewall software.

After that I would go to the manufacturer's website and make sure I have the latest drivers.


If these steps haven't helped, post back and provide your Operating System, computer model and router/modem model.
Also get some connection info:

• Click Start -> Run
• Type cmd in the textbox
• At the command prompt, type ipconfig /all and hit enter
• Right-click the titlebar of the command window and select properties
• Under the options tab, make sure Quick Edit Mode is selected
• Now highlight the results and right-click to copy it to the clipboard, and paste the results in your next post.

If you have a second laptop or a friend with a laptop that can work with you, refer to the following post for simple network connectivity troubleshooting using two machines:

http://www.bleepingcomputer.com/forums/topic133791.html

If these ideas make sense and you can follow them, post your feedback for additional advice. You can do all of the steps from your machine without having to have another machine present to connect with. That will save you time because you can gather a snapshot of the information for half of the troubleshooting without having a second machine to compare settings to.