Sadly no, Express Scribe is not compatible with Ds2 files. DS2 files are a proprietary format created when the Olympus DS-2400 is used to make dictations. After the dictation is created, the format can be converted to DSS or WAV format using the Olympus Standard software included with the DS-2400, which means you will have to request that the person creating dictations converts the files before sending them to you.