Installing Office Customization

Question

Name: From: file:///D:/Samples/TestUpdatedVersion/bin/Debug/TestUpdatedVersion.vsto

The customization cannot be installed because another version is currently insta

Answer 1

I had the same problem when deploying a new version of our VSTO word addin. After fiddling for 2 hours I found out that the Installation folder URL that you set in the properties of the solution (where it upgrades from) is case sensitive and stupidly needs to be the same case as the initial installation URL.

Answer 2

This error should only occur on your development machines.

From Microsoft's Troubleshooting guide for office deployments (http://msdn.microsoft.com/en-us/library/bb608594.aspx):

When you build an Office solution, the built version is automatically registered. If you have previously published and installed the same solution to your development computer, Visual Studio Tools for Office runtime detects that the installation path for the published version and the built version are different after the next build, rebuild, or publish. The error message says "the customization cannot be installed because another version is currently installed and cannot be upgraded from this location." Because rebuilding the solution updates the registry keys, it is necessary to uninstall the first version before publishing, debugging, or running the second version.

To prevent the message from appearing, create another user account on your development computer to test your deployment. Alternatively, you can uninstall the version from the list of installed programs on the computer before you next publish, debug, or rebuild the solution.

Answer 3

We have a number of products using VSTO on Office 2007, Office 2010 and Office 2013 on various Windows versions. The Deployment.AddInAlreadyInstalledException occurs often during deployments. The problem seems to occur especially on PCs with many install/deinstall cycles (such as of IT personnel itself). Often leaving me with gray or no hairs, since a re-install is not always easily possible and the source is unclear.

As there is not a silver bullet to fix any source of the problem (other than reinstalling Windows), I have gathered experiences in a blog post on steps to resolve AddInAlreadyInstalledException

Maybe this helps other users of VSTO and Microsoft Visual Studio.

Answer 4

This error can show up if you are trying to install/update a VSTO AddIn on the same machine where you've developed it, and it's caused by Visual Studio.

Whenever you build your AddIn in Visual Studio, it updates the registry key used by the AddIn thus breaking any install that you've done.

HKEY_CURRENT_USER\Software\Microsoft\Office\<Application>\Addins\<YourAddIn>\Manifest

The solution is to add a post-build event that would restore/set the registry key to the correct value. For example, if your AddIn is configured to be installed/updated from <YourPublishLocation>, the post-build event should be similar to:

REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\<Application>\Addins <YourAddIn>"
/v "Manifest" /d "<YourPublishLocation>" /f