Microsoft Exchange Server supports using distribution list, which is essentially a combination of several e-mail addresses that have been grouped together under a single e-mail address. The distribution lists accomplish the purpose of sending an email to all of the associated users in a single click. Each target recipient in the distribution list has a corresponding mailbox on Exchange Server computer with its local copy stored as OST file on client computer. In case if Exchange Server detects any of the recipient mailbox corrupted, the email will not be sent to any of the users in distribution list. Thus, to solve the issue, you might need to delete the corrupted mailbox. Though this solves the given problem, but also leaves the OST file orphaned on the client computer. This is where you can use Convert OST to PST utilities in case of backup unavailability.

As an instance of such problems, suppose you create a distribution list consisting of ‘n’ email adresses. You create a message and try to send it to this distribution list. Later, you observe that the message has not been sent and exists in local delivery queue of Exchange Server. Such issues indicate that there has been some problem in one or more of the recipient addresses.

Cause

Exchange Server fails to deliver the message to whole distribution list because of the primary reason that one of the mailbox linked with the recipient is corrupted, while the other ‘n-1′ recipients are in good condition.

Solution

Check for the errors that might indicate that a particular mailbox is corrupted. If you find the one, you need to delete it to solve this problem. To do so, follow these steps:

If the mailbox is not severely corrupted, try to move it to another mailbox store. However, if it is, you should delete it. You should first attempt to import the mailbox data to a PST file and then to a new mailbox on the same store.
Next, locate the ExchSrvr\Bin through command prompt and then run the below command for the affected mailbox store:

isinteg -s -fix -test alltests

Your email delivery problem is now solved, but as the after-effect makes the OST file inaccessible by Outlook. Microsoft Outlook at client computer of mailbox cannot access the OST unless it is converted to usable PST file. Thus, you need to use a Convert OST PST utility. The Convert OST to PST software perform safe OST conversion and make the file again usable within Outlook.

Stellar Phoenix Mailbox Exchange Desktop is an advanced utility that converts unusable OST to Outlook-usable PST. The Convert OST PST software supports MS Outlook 2007, 2003, 2002, and 2000. The tool restores all emails, calendars, tasks, and other items safely. The software is compatible with Windows 7, Vista, XP, 2003, and 2000.