This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice This article is not considered official documentation for K2 software and is provided "as is" with no warranties.


When opening K2 Designer, it displays the following error message:

"Could not load file or assembly 'K2Field.K2Forms.Controls.SetLanguage' or one of its dependencies. The system cannot find the file specified"



This error means that the Multilingual control from the K2 Community has been installed in the environment, and its assembly cannot be found. In most of the cases it happens when you restore an existing K2 database which contain control registration information (reference to assembly on a file system), but the assembly itself is missing in the required location.

All community projects/downloads fall outside of the scope of K2 support. By downloading any K2 Community project you are agreeing to our download license.

Troubleshooting Steps

Please follow the steps below to resolve this issue:

1. Download Multilingual control package from K2 Community (multilingual_1.91)

2. Copy K2Field.K2Forms.Controls.SetLanguage.dll which can be found under \K2Field.K2Forms.Controls.SetLanguage\K2Field.K2Forms.Controls.SetLanguage\Controls\bin\Debug and paste this file into the following locations:

- Program Files(x86)]\K2 Blackpearl\Smartforms Designer\bin\
- Program Files(x86)]\K2 Blackpearl\Smartforms Runtime\bin\

4. Perform an IISRESET

5. Clear browser cache and try accessing the K2 Designer again.