welcome to the forum.
How do I view a .DMA file.
DoorScope cannot read proprietary DOORS file formats. You have two possibilities to bring the contents of a DOORS module to DoorScope: 1) the "traditional" way: running the DoorScope DXL script from within DOORS which sends the data to the DoorScope ETL tool; the ETL generates the DSDX files which can be imported by DoorScope Viewer
2) the "new" way: export ReqIF format from DOORS; this format can directly be imported by DoorScope Viewer.
Hope this helps.