Timeout errors occurred when running a K2 Designer for Visual Studio process instance containing a high number of E-mail Events and e-mail sizes, combined with a slow SMTP server connection.  This will occur only when the K2 Server is running on the .NET4 Framework. The process instance will go into an error state and the errors will be visible in either Workspace>Management console>Workflow Server> Error Profiles or in Process Portal>Process Management>Error Logs.

Error Scenario

  1. From K2 Designer for Visual Studio, design a process containing E-mail Events, Notifications and escalations.
  2. Ensure all of the above mentioned e-mail bodies contain enough data to increase the size to at least 3MB.
  3. Deploy the process.
  4. Start several instances of the process to obtain high volumes of the E-mail Events executing.

Error Message

One of the following error messages might be displayed:

“Error in Processing: The server response was 4.7.0. Timeout waiting for client input”


“Service not available, closing transmission channel. The server response was 4.1.1 Connection timed out”


This Hotfix is contained within the latest K2 Update. Install the update package to resolve the error.  Perform an Update Design Templates function on the process containing the high number of E-mail Events in order for this fix to take effect.