This sounds like or at least similar to an issue I saw and have reported as a bug:
- if you have your news server "Connected while idle" sometimes you may end up with a yenc undecoded file. It may not be related to what I say, or something completely different, but try turning off the "Connected when idle" option in the servers and make sure you apply for each of your news hosts.
That *should* get rid of those pesky yenc files - otherwise, Alt.Binz will automatically decode a partially completed .rar (which might be missing one or more posts)
Also check setup > download and make sure the "When incomplete, position parts on correct position in file (yenc only) - pretty sure this is checked by default. It's pretty rare to see Alt.Binz output a yenc file, except in certain circumstances like I mentioned above, if you have "Connected while idle" set for your newshosts, uncheck the box and see if the same behaviour happens. rdl might be able to give another example where this might occur.
If you are seeing 430 errors in your log file and the nzb file you are trying to download is less than one hour old, then it is quite possibly a propagation issue - wait until the file is at least one hour old and try again.
It depends on where the source files are originally posted to and what tier 1 upstream providers they connect to, as to how quick propagation occurs. You'd need to give specifics on where the nzb came from or the actual file itself to be able to possibly track where it was posted to, and how long it might take to get to your news host.
Hope this helps.