Process %1 (PID=%2). Recipient object %3 read from %4 failed validation. DataValidationException will be thrown. Set event logging level for Validation category to Maximum to get additional events about each failure.

This Error event indicates that the recipient object specified in the event description is in an inconsistent state. An inconsistent state means that one or more attributes of the specified recipient object contain corrupted or invalid values. A recipient object is considered as Fully Consistent Object (FCO) if all its attributes contain valid values and these values are consistent with other attributes.

To determine which attributes or properties contain invalid values, do the following:

Caution   Incorrectly editing the registry can cause serious problems that may require that you reinstall the operating system. Problems resulting from editing the registry incorrectly may be unable to be resolved. Before editing the registry, back up any valuable data.

• Start Registry Editor (regedit).

• Locate the following registry key: HKLM\SYSTEM\CurrentControlSet\Services\MSExchangeADAccess\Diagnostics

• In the details pane, double-click on Validation and change its Value data to 5.

• Exit Registry Editor.

After the diagnostic logging level has been set to 5 (which is Maximum), review other Warning and Error events in the Application log to determine which attributes or properties contain invalid values.

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.