[MrForgetable]

Cliff notes: My Wi-Fi network problems are most likely because of Leopard, as Wi-Fi works flawlessly on XP/Boot Camp. Would a clean install of Leopard do the trick? and would a clean install wipe my Windows partition as well? If so, how do I back up a Windows partition if none of my drives at NTFS formatted? Thanks.

Leopard came out while I was at school (wired network) so I never realized that Wi-Fi had issues until I went home for Winter Break. The Airport connection was very spotty, often getting disconnected. But it could have been my old D-link router so I always played it down.

Now I'm back at school, but now when trying to connect to Wi-Fi networks here, I can't. The one network I connect to has a WPA password and every time I want to connect it says "Please enter your WEP password." Even when it said I was "connected" and had an "IP address" I was never really connected to anything. I figured maybe it was a MBP hardware issue now.

I was just about to go to the Apple Store down in SoHo today when I decided to go on my Windows/Boot Camp partition, for kicks. Haven't used it in a while. Turns out, Wi-Fi works perfectly on XP. No hiccups like I had at home on Leopard, no login and connection problems like I had here at school on Leopard.

So I was thinking a clean install of Leopard might do the trick. I do have things backed up in Time Machine on an External, but what would happen to the Windows partition? I don't have anything to backup an NTFS file system. Would a clean install even touch the Windows partition? Thanks for any advice.

[Cold Warrior]

Try an archive-install first.

[besson3c]

Test to make sure this problem also occurs under a different OS X account before anything else.

[MrForgetable]

Originally Posted by Cold Warrior 

Try an archive-install first.

That is what I did (minus Applications) when upgrading. Should I do it again?

[MrForgetable]

Originally Posted by besson3c 

Test to make sure this problem also occurs under a different OS X account before anything else.

So I guess it's not a User issue

[besson3c]

What IP address is being assigned to you? Can you ping your router's IP?

[MrForgetable]

192.168.1.102 (Linksys router)

I was once able to ping the router's IP, but I was never able to get past the setup page and it always took a long time. Now it just doesn't work at all. I'm going to go back on XP for a while.

[akuma-x]

Do not even bother with half of the things people are saying.
There is a big bug in 10.5 and 10.5.1 with Networking and locations.
I'm willing to bet that if you create a new new location it will resolve your issues.
You can even create a new location called "Automatic2" then delete the self created "Automatic" location and then rename "Automatic2" to "Automatic".
I have ran into this on many machines with my users and a new location always does the trick.
Apple really needs to fix this one in 10.5.2.

[MrForgetable]

I tried what Akuma said. It gets me an IP address and it allowed me to ping the router for a while, but it is extremely laggy, slow and spotty.

I was pretty excited when reading Akuma's advice because I also found out that I cannot archive and install from 10.5.1 down to 10.5 so I'll have to do a wipe if I decide to, after I figure out how to backup my Windows partition. Man, even my iPhone can get it right. Man, even WINDOWS can get it right. And I am a Windows hater! I'm going to sleep.

[akuma-x]

I would say at this point I would not do any wipe or reformatting until after Apple releases 10.5.2.
Unless you want to go through the work of putting everything back together. It has been noted that 10.5.2 will have some network stack fixes that will hopefully resolve your issue. Also I'm guesstimating here, but I think 10.5.2 will be out sometime next week.
I'm sorry that creating a new location did not work for you.

[MrForgetable]

10.5.2 does not fix this! I still have to unplug the power for the computer to connect to the router. When I sleep it then wake it, it won't connect, it asks for a "WEP password," instead of the WPA Personal password that I have made.