Topic
Workspace cannot be loaded. The following error message is shown:
"Could not load file or assembly 'SourceCode.Forms.Controls.Web.ControlPack.Worklist' or one of its dependencies. The system cannot find the file speciifed."

Instructions
Make sure 'SourceCode.Forms.Controls.Web.ControlPack.Worklist.dll' is present in iProgram Files]\K2\Bin\ControlPack Controls.
On K2 server, go to tProgram Files]\K2\Setup, open command prompt or Powershell with admin privileges, run the following:
controlutil.exe REGISTER -ASSEMBLY:"C:\Program Files\K2\Bin\ControlPack Controls\SourceCode.Forms.Controls.Web.ControlPack.Worklist.dll"
Make sure no errors are reported. After that restart K2 service and perform IISRESET.