MAPI message flags are mapped to Microsoft Mail 3.1 values to preserve backward compatability. All the flags are grouped together and encoded in a single byte. The mappings are as follows:
| MAPI message flags | TNEF flags |
|---|---|
| MSGFLAG_READ | fmsRead |
| MSGFLAG_UNMODIFED | ~fmsModified |
| MSGFLAG_SUBMIT | fmsSubmitted |
| MSGFLAG_HASATTACH | fmsHasAttach |
| MSGFLAG_UNSENT | fmsLocal |
These flags are defined in the TNEF.H header file.