Hi GuysI have 2 DC (win2k3), 1 exchange 2003 ent. in my network. 2 DCs are also DHCP and DNS. (A and B is name of the 2 DCs) A DC is PDC and Exchange works happily with A DC but not with B DC. If somehow A DC is not responding exchange will stop working, I can see that outlook 2003/2007 have disconnect status on them. I right clicked on properties of exchange server under systems manager, under directory access tab there are no servers registered. But if DC A is up then I can see DC A is listed as directory access server for all types likes of DC, GC, Config.I started loggin for exchange, this is I got:Event Type: InformationEvent Source: MSExchangeDSAccessEvent Category: Topology Event ID: 2080Date: 28/02/2009Time: 6:26:31 p.m.User: N/AComputer: Description:Process STORE.EXE (PID=584). DSAccess has discovered the following servers with the following characteristics: (Server name | Roles | Reachability | Synchronized | GC capable | PDC | SACL right | Critical Data | Netlogon | OS Version) In-site:dc1.domain CDG 7 7 1 0 1 1 7 1 this is the DC which works with exchange02.domain CDG 7 7 1 0 0 1 7 1newDC01.domain CDG 7 7 1 0 0 1 7 1newDC02.domain CDG 7 7 1 0 0 1 7 1newDC03.domain CDG 7 7 1 0 0 1 7 1Could you guys please shed some light on why that exchange does not pick up B DC as directory access server. This issue is bugging me for past few months, any pointers will be appreciated.Thanks a lot in advanceAjay

Hey Ajay,I could see from the event that Exchange has SACL right on DC1 but not on other DCs/GCs.(Server name | Roles | Reachability | Synchronized | GC capable | PDC | SACL right | Critical Data | Netlogon | OS Version)In-site:dc1.domain CDG 7 7 1 0 1 1 7 1 this is the DC which works with exchange02.domain CDG 7 7 1 0 0 1 7 1newDC01.domain CDG 7 7 1 0 0 1 7 1newDC02.domain CDG 7 7 1 0 0 1 7 1newDC03.domain CDG 7 7 1 0 0 1 7 1~ Follow step 4 available in Resolution of below KB to give correct permissions to Exchange on all DCs/GCs and wait for the replication.http://support.microsoft.com/kb/896703~ If above point doesn't help then check my second response in below thread to give raw levelnTSecurityDescriptorRead permission on OU, where these DCs are located.http://social.technet.microsoft.com/Forums/en-US/exchangesvrgeneral/thread/4cfab637-4d82-4c03-9362-5fa11777c70d/Amit Tank | MVP - Exchange | MCITP:EMA MCSA:M | http://ExchangeShare.WordPress.com

Hi Ajay, You can troubleshoot DC related issue according to 2080 event by refering to folloiwng KB:Event ID 2080 from MSExchangeDSAccesshttp://support.microsoft.com/kb/316300/en-usMike