Network error while opening workspace from extranet after upgrading into K2 5.6

  • 31 May 2023
  • 7 replies

Badge +6


I have recently upgraded K2 from 5.3 to 5.6. and after upgrade K2 workspace is not accessible from extranet and throws attached exception. we didn’t find any issues with internal network. below error is only when trying to open from extranet connecting with VPN. after upgrading and which was working  fine in K2 5.3.


A network error has occurred. unable to execute a server side operation.


can anyone help could be appreciated.

Best Regards,


7 replies

Userlevel 3
Badge +10

Was this an in place upgrade?  Or was K2 moved to another server during the upgrade process?

If there was a K2 server move, perhaps a network configuration was missed.


If no moves, have you also tested with the browser cache cleared?


Does the browser’s Developer Tools > Network trace indicates what it is failing on?  Is there a matching error in K2 HostServer log?


Is only the Workspace site exposed to the extranet?  If not, does the K2 Designer site loads?

Badge +6

Dear TinTex,

Thank you for your information.

This issue is only after upgrade and no change in the servers.

and we tested with static html by hosting in the same server which is working with out issue.

We have an issue only while connecting k2 forms, even K2 workspace is not loading and same issue with all the K2 forms.

From network trace, I could see AjaxCall.ashx is getting connection issue.

attached screen shots from both network trace and from console with developer tool.

Best Regards,

Badge +6



After a investigation, we found K2 smart forms are not loading if there is any smart objects are associated with in it and  its loading with out smart objects. I have logged a ticket and its been more than a week, but no support from the technical team.

please let me know, if any body has a solution for this issue.


Best Regards,


Userlevel 3
Badge +10


  1. Are you using Chrome?  Does clearing the browser’s cache help?
  2. Does switching to a different browser help?  Edge, Firefox, etc.
  3. From the screenshot, it looks like there is a ‘cache-fm.js’ file involved.  Are you using an F5 to expose K2 externally?
  4. As it is working internally, but not externally; this is likely related to the F5 configurations.  There may be a need to debug and possibly modify network/F5 configurations:
Badge +6

Dear TinTex.

Thank you for providing information.

We are facing this issue with all the browsers, Chrome, Edge and even with FireFox.

we do not have any issue with internally and yes, we are using F5 to expose K2 externally. 

and it seems to cache-fm.js file issue and I have attached browser issue, which is involved with cache-fm.js 

and we tried below workaround specified in below blog.

But as we are not hosting F5 in virtual server and we couldn’t able to progress much on this.

Request to let me know if you have any idea on this and there is no technical support from nintex team .

Appreciate your support.

Best Regards,



Dear @Thriveni 
F5 is changing the URL and forwarding/providing access to (exposing) the intial SmartForms call to allow loading a Form or View, but after that, SmartForms then gives the configured URL for the return calls from SmartObjects.

Since SmartForms does not know that the calls have been forwarded (or exposed) via a different URL, this then breaks since it is only available from the exposed:$$/Runtime/Runtime

And not from what is expected of

To solve this you must either:
Set up either a secondary site ( with configuration on F5 for the change

OR another SF Node that will have similar setup to Network load balancing ( where the URL is not modified in that way and the name is constant. Also with configuration on F5 for the change

OR Setup F5 so that it does not modify the URL in that way for SmartForms.

Badge +6

Thank you. Andrews.

F5 upgraded their environment and its resolved.

Best Regards,