I've seen the problem several times lately, hence the creation of this thread in the first place.

There aren't any specific steps that I've seen to trigger it other than marking messages as "Download & Save" and later finding the body downloaded but not decoded.
Manually performing a save works fine.
The AutoSave setting was left at 300 but I'm pretty sure more than 5 minutes elapsed since downloading the file in this case. In other cases it was hours that passed and decoding never ocurred. In the batch of files I had marked every one downloaded and saved fine except that last one.
There aren't any errors with saving that I know of. Plenty of free space, directory exists, file doesn't already exist. It should have worked but for some reason it didn't, hence my bug report.

Perhaps there should be some error message could be added in the Task Manager to help discover the problem. Certainly NewsPro is trying to perform the decode task but stops for some reason. (I'm not seeing any error messages with these incidents.)
I'm probably seeing this problem less than 5% of the time but it has happened several times in the past week. If I can discover any other pattern to reproduce the problem I'll post it here.