"Unexpected error" when opening a Group Email or submitting a job

Symptoms:

An unexpected SharePoint error occurs when  user  opens JungleMail Group Email popup or submits a Job.

1. Error message:

Error

An unexpected error has occurred.

Troubleshoot issues with Microsoft SharePoint Foundation.

Correlation ID: [Correlation ID]

Date and Time: [Date and Time]

2. Error message:

The server encountered an error processing the request. The exception message is 'Field RecipientEmails not found in item New Item fields. Parameter name: fieldName'. See server logs for more details. The exception stack trace is: 
[Code]

Occurs:

Occurs after JungleMail installation or upgrade.

Cause:

JungleMail infrastructure was not successfully provisioned to current Site Collection.

Outcome:

User is unable to open JungleMail Group Email popup or edit or submit a Job.

Solution:

1. Check if JungleMail solution is deployed to current Web Application. JungleMail solution should be deployed to Central Administration Web Application and all Web Applications where it will be used. Deploy JungleMail solution if not deployed.
   Central Administration > System Settings > Manage farm solutions > enova.sp.junglemail.wsp > Deployed To.
2. Repair JungleMail infrastructure:

• Repair JungleMail using installer.
  Run JungleMail installer and select Repair option.
• Reactivate JungleMail Core features.
  Deactivate and activate Site Collection JungleMail Core features on all Site Collections where JungleMail is used.