Load the multitrack recording into a computer. Convert the file format to one compatible with your particular multitracking recording software if necessary. Most multitrack recordings are stored in common sound file formats such as WMV or AIFF, but your particular recorder may need a specific format.
Open the multitrack editing software and import the song file. It will display with each individual track for each instrument and vocals. Usually, these will appear as horizontal graphic element boxes. They should be labeled according to which instrument or vocal appears on which track. For example, you may see a "Lead Guitar" track, "Backing Vocals" track, "Percussion" track and "Drums" track among others. In digital multitracking, there is virtually no limit to the number of recordable tracks you can use.
Isolate the drum track you want to remove. If the individual tracks are not labeled, click the "Mute" button on each track, then deselect this option for one track at a time. When you find the drum track or tracks you want to remove, remember where they are. Note that in some multitrack software packages each individual track is color coded for easy recognition.
Select the first drum track you want to remove. Usually, you can delete individual instrument tracks simply by hitting the delete key on your keyboard. If this does not work, look for an "Edit" menu or a "Track" menu and find the option for deleting tracks.
Save the multitrack recording without drums as a new file with a new name. If you intend to listen to this recording as a standard WMV, AIFF or MP3 audio file, you will need to mix down all the tracks to stereo and output it as a normal audio file.