How to Fix Outlook When the Msvcr80.Dll Cannot Be Found

Sometimes, Microsoft Outlook may refuse to start, insisting that the file "Msvcr80.dll" cannot be found. Even if this DLL is present in your "C:\Windows\System32" folder (the usual location for system DLLs), you may still receive the error. Fortunately you're not the first; it's a common error that can result from the installation of certain Outlook add-ins, some of which are installed as part of packages with other programs. Disabling those add-ins should allow you to start Outlook.

Instructions

1. Click "Start," then "Run."

2. Type "regedit" (without quotes) and press "Enter." The Registry Editor will appear. The nested folders in the left pane represent registry "keys," and clicking on a key will bring up one or more editable values in the right pane.

3. Navigate to the "Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Outlook\Addins\" key and click on it. A list of Outlook add-ins will appear below.

4. Find the add-in that's causing the problem. This may require some trial and error, but you can make an educated guess: This problem is known to be caused by various Norton security add-ins and also by the "eDataSecurity" add-in sometimes installed on Acer computers.

5. Disable an add-in by clicking on it, then double-clicking on the "LoadBehavior" value in the right pane. Enter a zero in the "Value data" field and press "OK." Close the Registry Editor.

6. Click the Start Menu and navigate to the following path: "All Programs" -> "Microsoft Office" -> "Microsoft Office Tools" -> "Microsoft Office Diagnostics." Follow the on-screen instructions to run Microsoft Office Diagnostics. This utility will repair the Outlook configuration files damaged by the add-in, and since you disabled the add-in above, the files will remain healthy. When the Diagnostics process is complete, Outlook should run normally.

Tips & Warnings

• If you have no idea which add-in is causing the error, disable all of them and then enable them one-by-one by entering a 1 in their "LoadBehavior" values. After enabling each add-in, run Microsoft Office Diagnostics, then open Outlook, close it, and open it again. Repeat this process until Outlook refuses to start the second time. Whichever add-in you last enabled is the problem; leave that disabled, and reactivate the others.

References

• Slipstick: Outlook Error: This application has failed to start because MSVCR80.dll was not found.
• Andremiller.net: Starting Microsoft Outlook 2007 on Acer Vista system gives MSVCR80.dll was not found error