Cause 1
This issue may occur if Microsoft XML Core Services (MSXML) 4.0 Service Pack 2 (SP2) is not installed or the installation is corrupted.
Cause 2
This issue may occur if the MSXML components have trouble communicating with the Microsoft CRM Outlook client.
Cause 3
This issue may occur if there is an unexpected line of code in the Isv.config.xml file. For example, this issue may occur if the following line of code appears in the Isv.config.xml file:
xml version="1.0" encoding="Windows-1252"
Because there is an unexpected line of code, the file cannot be successfully parsed. When the Outlook client tries to load its forms, the Outlook client cannot build the form because it has a malformed XML document.
Cause 4
This issue may occur if the Microsoft CRM 3.0 Web site is using the Microsoft .NET Framework version 2.0 instead of .NET Framework version 1.1.4322.