This is perhaps a buglet report. I'm not too worried, just thought it should be reported.
The source staff is a certain seasonal tune in A major which starts with E an octave below the treble clef. It has no accidentals, double flats or double sharps.
Using 2.75a Beta 7, I transposed it into all major keys, favouring minimum sharps and flats, by copying it to 11 staffs and transposing each by +1, +2, or +3 half tones, etc., up to 11 half tones.
The +11 semitones transposition triggered the Transpose Warning error message that the E would not transpose properly. Clicking "Show Next Problem" highlighted all the notes, one at a time, as a problem, for the first 4 bars (I stopped there). When I clicked on Proceed with Transpose Anyway, the transposition worked just fine.
I tested a workaround, transposing the source staff up 12 semitones and down one, and got no error messages.
I'm not sure why the error message appeared. It could be a one-off glitch or it could be a minor bug.
Well, you didn't get an "error message." You got a warning. Thin gruel for a buglet report. More like click bait :)
Warnings or error messages? I would think the terms are synonymous.
I agree it's very minor, but it's still a glitch. I don't think it needs to be high priority, but if tweaking something fixes it, then it should be tweaked at some time in the future.