Error: General license key exception: No valid license key found


When trying to create an instance of the ExcelApplication or ExcelTemplate objects, the following error is returned:

General license key exception: No valid license key found.

This can happen if you are trying to use an OfficeWriter dll that is not the same version as the license key in the registry.

A common scenario where this occurs, is upgrading to a new version of OfficeWriter. When the old version of OfficeWriter is uninstalled and a new version is installed, the dlls in your projects are not automatically updated. This means that your projects may have references to the old dlls (say v4), but the license key in the registry is for the new version (v8).

Update April 4, 2013: If you are running a 32-bit application with OfficeWriter on a 64-bit operating system, you may encounter this error message, even though the license key is in the registry and matches the version of OfficeWriter being used. If you experience this issue, please contact us.


There are 2 options:

  1. Update the references in your projects to point to the new OfficeWriter dlls. (Dlls can be found under Program Files\SoftArtisans\OfficeWriter\bin).
  2. Add the license key for the old version with the License Key Manager to run both versions of OfficeWriter. For more information about running different versions of OfficeWriter side-by-side, refer to this post.

To add a license key with the License Key Manager:

  1. Locate LicenseManager.exe either from Start > Programs > SoftArtisans > OfficeWriter or from Program Files\SoftArtisans\OfficeWriter.
  2. If you are installing on Windows 7 or Windows Server 2008, right click LicenseManager.exe and select ‘Run as Administrator’. Otherwise, double-click to run the installer.
  3. Click the Add/Update Key button to add the license key.
  4. After the license key is added, you should see license keys for the old and new version registered.

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