You receive a "Can't open this item" error message when you try to open a posted item in a public folder in Outlook

Because of an issue in Microsoft Exchange Server 2003 or in Microsoft Exchange 2000 Server, when you try to open a posted item in a public folder in Microsoft Outlook 2000 or in a later version of Outlook, you may receive one of the following error messages:

Error message 1

Error message 2

If you try to manually open the posted item on a server that is running Microsoft Exchange Server , you may receive the following error message:

This issue occurs when you use the GFI MailSecurity for Microsoft Exchange/SMTP version 7.2 antivirus program on the computer that is running Exchange 2003 or Exchange 2000. The GFI MailSecurity antivirus program puts file locks on files that are attached to the posted item.

You can disable the GFI MailSecurity antivirus program when an Exchange server has been temporarily isolated from the network. To do this, follow these steps.

Step 1: Disable and stop the GFI MailSecurity version 7.2 service

To do this, follow these steps:

1. Click Start, click Run, type services.msc, and then click OK.
2. Double-click the service for GFI MailSecurity version 7.2.
3. On the General tab, click Disabled in the Startup type list.
4. Click Stop, and then click OK.
5. Close the Services console.

Step 2: Create a registry value to enable the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\VirusScan registry subkey

To do this, follow these steps.

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\VirusScan
3. Set the value to the following:
   • Value name: Enable
   • Value Type: REG_DWORD
   • Value Data: 0
   Note After you configure this registry value, you must restart the computer.

According to GFI software, you can both avoid and resolve this issue if you use the following methods in the order that they are presented:

• Upgrade to the latest version of the GFI MailSecurity antivirus program (Version 8).
• Follow the information in the articles at the following GFI Web sites:
  http://kbase.gfi.com/showarticle.asp?id=KBID002057
  
  http://kbase.gfi.com/showarticle.asp?id=KBID001762

You can also resolve this issue if you remove and then reinstall the GFI MailSecurity antivirus program. For more information about the GFI MailSecurity antivirus program and for GFI MailSecurity product updates, visit the following GFI Web site: Microsoft provides third-party contact information to help you find technical support. This contact information may change without notice. Microsoft does not guarantee the accuracy of this third-party contact information.

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base: