Notes about the DTF file extension:
Incorrect file associations could be the result of underlying issues within your PC system. As such it is highly recommended to scan your PC for invalid registry entries
, unused processes and other unfavourable system settings to identify slowdown issues.
The DTF file type is primarily associated with 'ACDSee' by ACD Systems Ltd.. A thumbnail database that tracks what you do in ACDSee. If the program starts to slow down you might recover some speed by deleting this and the .DDF associated file.