Really weird ADSL connection issue

[ABOzIT]

I'm having issues with my ADSL connection that not even my ISP can figure out. The whole problem just doesn't make any sense.

Internet was working one morning with my brand new Netcomm NB5580W, came home that afternoon and it wasn't. No changes to modem settings as I wasn't even home. New modem worked for 4 days!!

The PPPoE client in the modem indicates "Connecting" but never connects. The ADSL link light on the modem is on steady so the line is in sync. Tried my old D-Link DI624S and that did exactly the same thing so I'm not thinking that it's a modem problem.

Now the really weird part - Set the modem to bridged mode and tried the native PPPoE client in XP and to my surprise it connected fine.

Now, I'm a network admin so I'm not a net novice. I've tried everything I know - reset modem to factory settings, flashed firmware, tried wired & wireless, everything fails to resolve the issue.

I'm at the end of my patients on this one as it doesn't make sense to me at all why this won't work. What is the difference in PPPoE between the modem doing it or XP doing it over a bridged modem??? Why does one work when the other fails???

If anyone has any suggestions I would really appreciate your input.

Thanks!!

 

[KiscoKid]

I've seen issues in the past with pppoe and MTU settings. pppoe uses a smaller MTU than standard Ethernet and this can cause issues with poorly-configured network devices.

I'd check the MTU setting on the your modem there and try setting it to the advised MTU (1492) if necessary. It may help...

 

[ABOzIT]

Thanks KiscoKid for your suggestion. Yeah, I've been down to MTU path. It's set to 1492 and I've even tried with the MTU disabled but still no joy.

The really frustrating part about this problem is that it was working fine and now it's not and I've not touched any settings on the modem. My old modem that was also working before I replaced it is not working either. It's really quite crazy!!

Cheers!

 

[hispeedtech]

ABOzIT, you say the modem won't connect, but you connected fine using XP connection in bridge mode? Sounds to me like your username/password got corrupted in the modem. Try reentering them in the modem and see if you connect. This is especially true if you reset modem, as most modems wipe out the PPPoE username and password after you reset them. I wasn't able to get much info from the Netcomm website, as their servers seemed to be having some issues, but I did find out that in a CNET review they had problems with this modem right off the bat. The replacememnt worked fine however.
If you can get connected through your modem, don't forget to delete the connection in XP to avoid conflicts.
G'luck

 

[ABOzIT]

Problem is now solved - well sort of!!

I am now connecting using PPPoA instead of PPPoE. This still doesn't explain why PPPoE was working fine one morning and not working that afternoon without me even touching the modem. It still doesn't explain why the native XP PPPoE client could connect using the same modem in bridged mode!!

Thanks everyone for their suggestion

Cheers!

 

[plshlpme]

any chance they are looking at your mac address...
can you try cloning your XP pcs mac onto the router...