Error: "Could not decrypt file discovery whitelist after sync"

Under the MID server record in the "MID server issues" tab you see the following error:

"Could not decrypt file discovery whitelist after sync".

All

Cause 1:

• This happens when the MID server tries to decrypt files that are trying to be synced from the instance before it had a chance to be validated. 

Cause 2:

• The issue is caused by the fact that the instance will return nothing if the plugin "com.snc.discovery.file_based_discovery" doesn't have a license and the code on the mid server doesn't handle the error correctly so that the error message is misleading.
• Please take a look at the sys_web_service script GetMIDInfo. When MID server starts, it will send a SOAP request to instance asking for updating file discovery allow-list. The request will be handled by the following function in GetMIDInfo: 
  

  function updateFileDiscoveryWhitelist() { 
  var havelicense = sn_lef.GlideEntitlement.hasBetaLicenseForApp('com.snc.discovery.file_based_discovery'); 
  if (!havelicense) { 
  response.midInfo = null; 
  return; 
  } 
  var agent = request.agent; 
  var doc = MIDServerInfoAccessor.updateFileDiscoveryWhitelist(agent); 
  response.midInfo = doc; 
  } 

  Since there is no license for this, it returns a response with an **empty** midInfo and the MID server will see that as a mid server issue, this can be ignored.

Cause 1:

• Make sure the MID server is validated
• Manually resolve the Issue on the instance
• Restart the MID Server, the issue should not come back anymore

Cause 2:

• On the script comment out the license verifying code to work around it. (Please note the update to this file during platform upgrades might be skipped)
  
  OR
  
  
• Add a business rule to ecc_agent_issue (MID server issues) table to automatically change the state of that particular error message to 'Resolved' so it does not appear on the MID issue list as a 'New' issue any longer. 

If the above performed and still have some issues, please follow the below 

• Stop the mid server from the host machine, deleted the Keystore folder and started the MID- server service.
• The Keystore folder will be created automatically
• Now login to the ServiceNow instance and validate the mid server 
• Wait for 2-5 minutes and the error will disappear from "MID SERVER ISSUE TAB"