When using Content Manager Outlook Integration, user is presented with error: There is an error in XML document (0, 0) Further details from the integration log shows that it is due to root element is missing.

Environment

Content Manager 9.4

Situation

When user is using Outlook with the presence of Content Manager Outlook integration, user can encounter the error below while in operating  : 

"There is an error in XML document (0, 0). ---> System.Xml.XmlException: Root element is missing"

User can encounter the error under these circumstances:

1, When user starts up Outlook session, user is presented with the error in a pop-up dialogue.

2, When user replies/sends/creates an email, user is presented with error in a pop-up dialogue.

3, When Content Manager  Add-in is disabled but user checks the Content Manager Outlook integration log, the error above shows up.

In the integration log more detail is given  : 

System.InvalidOperationException (-2146233079): There is an error in XML document (0, 0). Root element is missing. Occurred on line: 0 at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
at System.Xml.Serialization.XmlSerializer.Deserialize(TextReader textReader)

Cause

The error indicates that one or more of the following XMLs under user AppData Content Manager OfficeIntegration folder is corrupted:

C:\Users\<username>\AppData\Roaming\Micro Focus\Content Manager\OfficeIntegration

- CheckinPlaces_<DBID> and CheckinStyles_<DBID> 

- checkInOnSendInfos

- managedDocs and managedTemplates

Find resolution here