當開啟Outlook 出現Scanemal.dll or Scanotlk.dll error when opening Outlook (Scanemal.dll or Scanotlk.dll cannot be installed / loaded / found or is missing)

Environment
For details of all supported operating systems, see KB51109
Microsoft Outlook XP
Microsoft Outlook 2007
Microsoft Outlook 2003
Microsoft Outlook 2000
Video Tutorial
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TU30048 - Resolving VirusScan errors when opening Microsoft Outlook
Problem 1
When opening Microsoft Outlook, an error message is displayed. The exact error message varies between Outlook versions, but will be similar to one of the following:
•The add-in \scanemal.dll could not be installed or loaded

•The add-in \scanemal.dll could not be found

•Unable to load \scanemal.dll You may be out of memory out of system resources, or missing a dll.file

•Could not load plugin \Scanemal.xxxxxxx.dll

The above also applies to the file: ScanOtlk.dll

•The Add-in "Outlook Scan" (\Scanotlk.dll) cannot be loaded and has been disabled by Outlook. Uninstall the Add-in if no update is available.
Problem 2
This issue occurs only on shared computers with multiple user profiles.

The error occurs after a McAfee product upgrade, when older McAfee Anti-Virus software is uninstalled (and a newer version is installed).
Cause
Microsoft Outlook maintains a local disk cache of Outlook Add-ins, called Extend.DAT. Outlook uses the cache to locate those add-ins and if a specific add-in is no longer present, one of the error messages detailed above is displayed.

For a vendor who integrates an add-in with Microsoft Outlook, this issue arises when:
•The install path of the product changes
•The dynamic link library (DLL) for the add-in changes name
In VirusScan Enterprise 8.7i, McAfee utilizes the Microsoft-approved manner of updating the Exchange Scan add-in. However, this method only works for one user; The Outlook error will be seen by other users of the same computer.
Solution
This issue is resolved in VSE 8.7i.

It is possible to encounter the issue when you upgrade to 8.7i, but it will no longer be possible to encounter the issue in future upgrades.
VSE 8.7i includes new architecture for how the Exchange Scan add-in works. This architecture change works around the design of Microsoft Outlook that causes the errors to occur.

If you have already encountered this error, see the workarounds below.
Workaround 1
Install Microsoft Office 2003 Service Pack 3.

Microsoft Office 2003 Service Pack 3 may also help to resolve this issue, although this has not been officially confirmed.

If you are using Office 2003, you can download Service Pack 3 from the Microsoft web site: http://office.microsoft.com/downloads/default.aspx
Workaround 2
Delete the EXTEND.DAT File.

The EXTEND.DAT file includes a cache of Outlook add-ins that are selected in the Add-in Manager. Deleting EXTEND.DAT will cause Outlook to verify the selected extensions and recreate the file when Outlook is next launched.

To delete the EXTEND.DAT file:
1.Close Microsoft Outlook.
2.Click Start, Search, For Files or Folders.
3.In the All or part of the file name box, type extend.dat.
4.Click More advanced options and select the following:

•Include subfolders
•Search hidden files and folders.

NOTE: In some cases, EXTEND.DAT is hidden by the operating system. Selecting this option ensures that all instances of EXTEND.DAT are found.

5.In the Look in list, select My Computer, and click Find Now.
6.In the search results, right-click each instance of EXTEND.DAT and click Delete.
NOTE: If more than one profile exists in Outlook, an EXTEND.DAT file will be created for each profile. If the installed location of the VirusScan software changes, delete EXTEND.DAT for each profile on the system. By default, EXTEND.DAT can be found in the following locations:
•Windows XP:
\documents and Settings\\local settings\application data\microsoft\outlook

•Windows Vista:
\users\\appdata\local\microsoft\outlook
Workaround 3
Remove the Exchange Scan Add-in via Outlook.
To remove the Exchange Scan Add-in:

1.Open Microsoft Outlook.
2.From the menu click Tools, Options.
3.Click the Other tab.
4.Click Advanced Options.
5.In the lower part of the window click Add-in Manager.
6.Deselect Exchange Scan.
7.Click OK until all windows are closed.
8.Close and reopen Outlook.
For Outlook 2007:
1.Open Microsoft Outlook 2007.
2.Click Tools, Trust Center, add ins.
3.Click the option Manage, which is located in the bottom right corner.
4.From the drop-down list, select Exchange Client Extension and click Go.
5.In the Add In Manager window, deselect Exchange Scan and click OK.
6.Close and reopen Outlook.
Workaround 4
Delete the EXTEND.DAT File via ePolicy Orchestrator (ePO).

If multiple computers are affected by this issue, McAfee ePolicy Orchestrator can be used to quickly delete EXTEND.DAT on all affected computers. After the file has been removed, a new instance of EXTEND.DAT will be created the next time Microsoft Outlook is opened.

To configure ePO to delete EXTEND.DAT from client computers using:
•ePolicy Orchestrator ePO 3.6.1, see KB59988.
•ePolicy Orchestrator ePO 4.0, see KB60069.

When the Task and Policy changes are deployed to client computers, the on-demand scan runs and completes very quickly. The scan deletes all copies of EXTEND.DAT on the client.

When Microsoft Outlook next launches, it will recreate EXTEND.DAT with the new information.
Previous Document ID
KB45646