Dpatch is a tiny utility to aid printing through a dongle. Some early dongles did not allow printing until a copy of Impression or ArtWorks had been run. If you have such a dongle, then running DPatch in your boot sequence should clear the problem.
The software is stored in a Zip archive, which can be read using SparkPlug, or any of the Spark family. SparkPlug may be downloaded from David Pilling's Web site, among others.
Extract the contents of the archive to another disc, and make sure that DPatch is run during your boot sequence. Note that the main reason that the file is compressed is to preserve the file type - at 279 bytes the archive is actually larger than the compressed file.