The extension C:\Programs... could not be installed and/or

This error message occurs if an Add-in was not correct uninstalled.

Sometimes a virus scanner prevent the correct unregister procedure of a dll, sometimes user delete folders without using the deinstallation routine (Control Panel or Program Group).

In this cases you receive the following error message (up to Outlook® 2003): "The add-in "C:Program Files (x86)Common FilesESM-Tools SharedSafeOut..." could not be installed or loaded. This problem may be resolved by using Detect and Repair on the Help menu."

Detect and Repair does not fix the problem in this case. Outlook® 2007 and higher gives the user a much more better description of the problem: "The Add-in "ESM-Tools Helper Outlook Extension" (C:Program Files(x86)Common FilesESM-Tools SharedSafeOutlook.dll) cannot be loaded and has been disabled by Outlook. Please contact the Add-in manufacturer for an update. If no update is available, please uninstall the Add-in."

In this described case the problem causes through an incomplete uninstall and is therefore not the solution of the problem. You can simply fix an incomplete uninstallation by installing the program again and then try an uninstall by deactivated virus software etc.

If this will not work you can manually deactivate the Add-in in Outlook®:

Up to Outlook® 2003: Tools -> Options -> Other -> Advanced Options -> Add-In Manager...

Outlook® 2007 and higher: Tools -> Trust Center... -> Add-ins -> Manage -> Exchange Client Extensions -> Go...

Uncheck there the Add-in "ESM-Tools Helper Outlook Extension"