Unfortunately NI Multisim files are not backwards compatible, meaning you cannot produce version 8 (.mp8) from version 10 (.mp10 file). If you need version 8 file, you will have to recreate the project using that particular version of the software. It is unlikely that some converter for mp10 to mp8 conversion exists.
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
If you find entry that you feel is flagged as bad wrongly, please tell us in the discussion below with as much as information as possible so we can fix it.