Email being block by att.net

Description:

Users are having issue when sending email to certain domain. From the undeliverable message, you could see, " is blocked. For information see http://att.net/blocks'>". You've check with known blacklist provider and none of them have your IP listed.

Resolution:

To remove your IP from their list is through their website http://att.net/blocks. Choose Tools for administrators of mail systems whose messages have been blocked. Fill in your IP address, name, contact number, and the error message that you received. After that click submit. It would take a couple of days for them to remove your IP.

Email being block by 88.blackzap.net – Frontbridge

Description:

Users are having problem sending email to some domain. From the error message you could see “smtp; 550 Service unavailable; Client host [xxx.xxx.xxx.xxx] blocked using 88.blacklist.zap; Mail From IP Banned To request removal from this list please forward this message to delist@frontbridge.com>”. You’ve check with known blacklist provider and none of them have your public IP listed.

Resolution:

The only way to get your public IP remove from their blacklist is through email. The list is proprietary and not open for public. You need to send them email asking for delisting and they will reply back to you in one business day. This is the case if you get listed the first time. But if you IP get listed again, the process would be more difficult and take much longer time.

Frontbridge is owned by Microsoft and its part of their Exchange Hosted Services. However the support seems only available on US working hour’s time. Other than that, there’re some false positive that could make good legitimate email being blocked.

Cannot start IPSEC service error. The system cannot find the file specified.

Description:
Suddenly you cannot logon to the domain from a server. You cannot ping it, even though the network card is connected to the network and functioning normally. You can ping to self from the server. No firewall blocks the connection. When looking through event viewer, you notice 2 errors were log; Event ID 7023 and Event ID 4292 (IPSec driver has entered Block mode). Both are related to IPSEC. You check the IPSEC services and found that you cannot start it. There’s “The system cannot find the file specified” error.

Resolution:
The problem occurs when there’s corrupted file in the policy store. The file may become corrupted if an interruption occurs when the policy being written to the disk. To solve it, please go to HKEY_LOKAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\IPSec\Policy\Local. Delete this subkey (if exist). After that, rebuild the new local policies store. To do that, click Start > Run > type regsvr32 polstore.dll. Try starting the IPSEC services again. All issue should work well now.

Event ID 9325 logged when running Exchange Offline Address Book (OAB) generator

Description:
You notice that there are a couple of event ids 9325 being logged at your exchange server. All function seems to run normally. The error message shown something like “OALGen will skip user entry person name in address list '\Global Address List' because the SMTP address is invalid”.

Resolution:
Using Adsiedit.msc console, go to the SMTP proxy address attribute and proxyaddresses attribute. Check the value and correct or remove any invalid SMTP address. You can refer to the Microsoft KB 926206 (http://support.microsoft.com/?id=926206) for detail info for how to resolve these errors.

Event ID 9321 logged when running Exchange Offline Address Book (OAB) generator

Description:
You notice that there are a couple of event ids 9321 being logged at your exchange server. All function seems to run normally. The error message shown something likes “OALGen could not generate full details for entry person name in address list '\Global Address List' because the total size of the details information is greater than 64 kilobytes.”

Resolution:
The most common cause for this is a large number of certificates published for the user, causing their details to be over the 64kb limitation for the details in the OAB. There is no way to increase this limit, so the solution is to remove any unneeded certificates from the users so that we get the details under 64kb.
To clean out the certificates:
- In ADUC, make sure View, Advanced Features is checked.
- Go to the properties of the user.
- Published Certificates tab.
- Remove any unneeded/expire certificates.