Dealing with numerous "Callback" errors in Service Center.

Dealing with numerous "Callback" errors in Service Center.

  
Hi everyone,
 
I am writing this post to let you know how to solve a common issue that is reported in the OutSystems Platform regarding "Callback errors".
 
The symptom is that you start seeing a lot of messages in the Service Center Error Log similar to the following:
 
Error invoking callback OutSystems.HubEdition.RuntimePlatform.Callbacks.StaticContentCallback on event PageRender: The remote server returned an error: (500) Internal Server Error.
   at System.Net.HttpWebRequest.GetResponse()
   ...
 
Or maybe:
 
Error invoking callback OutSystems.HubEdition.RuntimePlatform.Callbacks.ECT.ECTGetHtmlCallback on event SessionStart: The remote server returned an error: (404) Not Found.
   at System.Net.HttpWebRequest.GetResponse()
   ...
 
The cause for these "Callback" errors is usually in the Embedded Change Technology and/or Embedded Process Automation applications (ECT and EPA), which are included in the Systems Components solution bundled with the OutSystems Platform.
What may have happened is that a user deleted or disabled one of these applications in the environment, but some of their callback mechanisms are still at place.
 
The best solution for these errors is to keep these applications published in the environment and disable the features you are not using in the corresponding back-offices:
 
  1. Access Service Center and make sure that the "Embedded Change Technology" and "Embedded Process Automation" applications are published.
    If one of them (or both) are not available, you can always republish the System Components solution that is included in the OutSystems Platform Server.


     
  2. If you wish to disable the ECT features, access the "ECT_Provider" back-office through a browser, and make sure that all the configured "Rules" are disabled (usually, if you never used ECT, you will only have one default rule that should be disabled):


     
  3. If you wish to disable the EPA features (Business Process Technology), access the "EPA_Taskbox" back-office through a browser. Make sure to "Activate EPA Administration" and make sure that EPA is "Not Active" for all eSpaces (if you have never used EPA, then after activating Administration  all eSpaces will be disabled by default):



 
After all of this, you should stop seeing the "Callback" errors in Service Center!
 
I hope this helps.
 
Cheers!
 
João Proença