OK, so this error perplexed me for a while until I realized the naming in the "Multi Encoder" encoders seems to do something completely different.

First of I am not using a network drive, just a local write on my disk. So here is what is breaking and was driving me crazy...

When using Dynamic Naming in "Multi Encoder" with a "-" character for some reason it is changing the "-" character to a "/" character, this also occurs when the the track title has a "-" character or a "/". This is a fresh install with no settings tweaked, only after the struggling with this for a while did I try to tweak some things, like changing the "CD Ripper Options -> Meta Data & ID Tag Character /Word Replacement" and the "CD Ripper Options -> Filename Restricted Characters" options to try to prevent this. Attached are the two dialog screen shots, because seeing is believing, these are the settings I had to begin with, and the ones I set them back to. Changing these did not seem to have an effect on the above problem. Any text in the file name with the "-" character is being converted to "/", and also when a file name has the "/" character in it it is not being removed. I am using version: dMC-R16.2-Ref-Trial.

dbpoweramp-Meta_Character_Word_Replacement_Dialog.png
dbpoweramp-File_Name_Character_Replacement_Dialog.png

I have verified this seems to be a problem ONLY with the naming used in the "Multi Encoder" when using the exact same naming convention as the regular encode (Literally copying and pasting it) it fails . I have only tested this for FLAC and MP3, but I suspect it is a Multi Encoder issue. Please verify you can recreate the problem.