Exchange Help

**dddwarp** · May 12th, 2004, 02:59 PM

I need help

(I know, I could get in trouble with that remark)! We are having an issue with our email system. It seems that about once a day throughout the network clients loose their connection with our exchange server. It is as different times and at different locations (VLANS). Also one clients keeps working and while one stops. The clients need to close and then reopen their outlook. Also sometimes email get "stuck" in the outbox and clients need to copy and paste old email into new email to get it to send. The emails and other information is stored on the exchange server. It is annoying because we cannot recreate it and the other technicians are saying it is a network problem. I believe the network is running fine. Here are the facts:

Exchange 2000
Server is a member of a Windows 2000 child domain
All clients are pointing to the Domain Controlers for DNS
Clients are Ooutlook 2003
2 Frontend and 1 backend Exchange servers
Clients connect by exchange service and not POP3

Like I said, it works most of the time but once a day it "blinks". Any help in where to start looking. I have examined the DNS both on our public DNS and AD DNS and find no problems. Thanks!

**silencio** · May 12th, 2004, 06:07 PM

I'd start by looking at the event logs of the effected machines and the exchange server during those periods. How many global catalog servers do you have and what boxes are they on? Are there any communication errors betweent the child domain and the root of the forest? Run dcdiag /e /v and netdiag /v and make sure you have lots of buffer room in your command prompt. There's also a switch to log these I don't remember what it is but running it with /? will give you the switches. If you don't have the apps you can install them from the original cd in \i386\adminpak.msi or support\tools\suptools.msi

They don't need to be installed on the specific server. You can install to another machine and specify which server(s) to run them on as long as you have rights.

**amadeus_hack** · May 12th, 2004, 08:51 PM

We have had the EXACT same problem and have traced it back to MASTER BROWSER ELECTIONS on our network. Every time certain clients would connect up to the network (Mostly laptops over a VPN connection), they would cause a browser election and for some reason it would kill all 200 users on our email server. They would have to close out outlook and open it back up after the browser election ceased. Check your event logs on the domain controller and see if there is a browser election happening around the same time the email seems to act up. If it is the case find the offending computer (or computers) and turn off the browser service (there is a registry key you can edit but I can't remember it). We spoke to MS about this and turning off the service will do the trick. Also look into how many WINS servers you have set up, too many on the network will cause problems according to MS, I forget the actual number but one WINS server can serve thousands of clients and we had something like 5 for 600. I hope this helps.......please let me know how this works out for you.

Originally Posted by dddwarp

I need help

(I know, I could get in trouble with that remark)! We are having an issue with our email system. It seems that about once a day throughout the network clients loose their connection with our exchange server. It is as different times and at different locations (VLANS). Also one clients keeps working and while one stops. The clients need to close and then reopen their outlook. Also sometimes email get "stuck" in the outbox and clients need to copy and paste old email into new email to get it to send. The emails and other information is stored on the exchange server. It is annoying because we cannot recreate it and the other technicians are saying it is a network problem. I believe the network is running fine. Here are the facts:

Exchange 2000
Server is a member of a Windows 2000 child domain
All clients are pointing to the Domain Controlers for DNS
Clients are Ooutlook 2003
2 Frontend and 1 backend Exchange servers
Clients connect by exchange service and not POP3

Like I said, it works most of the time but once a day it "blinks". Any help in where to start looking. I have examined the DNS both on our public DNS and AD DNS and find no problems. Thanks!

**dddwarp** · May 13th, 2004, 08:10 AM

Thanks guys, I will do some research this morning and I hope to solve the problem. silencio, I remember netdiag but not dcdiag. I will look implement both. And about master browser and WINS, I will also look into both. I am not exactly sure about the servers since I am the network "guy" and not the server guy. But it seems when they are stumped, they blame the network and I have to fix it. Again thanks and I will get to you.

**drewmaztech** · May 13th, 2004, 03:22 PM

I know this isn't a fix but a nice feature of Outlook 2003. We have all the clients setup in "cached mode" even though the server is almost always available. That way if the server does hiccup or we reboot it, they just get a little note saying theyre offline and the emails will reside locally. Then is attempts reconnecting every minute or so.

Just a nice buffer so no emails get hosed en-route.