During Exchange Server 2013 setup you may encounter error code 8224 running ldifde.exe to import schema file.
When you are preparing an Active Directory Forest for Exchange Server 2007 installation you may encounter an ldifde.exe error importing the schema file.
This article explains which upgrade paths are supported from Exchange 2003 to Exchange Server 2010, and under what scenarios you would want to use Exchange 2007 as an interim upgrade path.
An Exchange Best Practices Analyzer bug gives a misleading error report in scans of Exchange Server 2010 organizations.
During Exchange Server 2007 schema extension you may encounter a security descriptor error which will cause setup to fail.