I use Constant Contact for email marketing. I have integrated constant contact to display in a contact view in the field, "Campaign History." It has been working for over a year. All of a sudden it is no longer displaying properly. I have attached an image of what visual force is now displaying the field. 



Error code from scrolling:
only whitespace content allowed before start tag and not E (position: START_DOCUMENT seen E... @1:1)
Error is in expression '{!FetchNextSummary}' in page ctct21:contactcampaignhistory: (CTCT21)

An unexpected error has occurred. Your solution provider has been notified. (CTCT21)

If you have an idea of what may be causing an error, that would be extremely helpful. 

Does anyone know why an email alert triggered from a workflow would not be creating the associated activity history? Emails sent through the interface, through Apex, and through the API are all logged in activity history (when the appropriate information is set). The email alert is set to be sent to the Contact Email (standard) field.

Thanks!