In message , masonc
writes:
On Sat, 05 May 2018 14:59:59 -0700, masonc
wrote:

Can renaming a file change its format?

Changing file names in Win7pro caused my mp3 player
to reject them as "format not correct"

Files transfer normally otherwise.

Computer disks NTFC. Player is FAT32, internal and card.

These are mp3 "music" files (actually voice: stories)

What is the nature of the renaming you're doing?

If you're changing the extension on the file name (either to .mp3 _from_
something else, or from .mp3 _to_ something else), then I'm not
surprised.

If you're changing the part of the name before the dot, _some_ players
may be fussy about (a) filenames longer than 8 characters (b) filenames
with certain characters in them.

To answer your first line: I've never experienced _any_ situation where
changing the name of a file - whatever the nature of the change - alters
its contents. However, it often (I'd say usually) alters what the device
or OS handling them _expects_ to be the contents, if the change is to
the extension at least.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

To keep leaf vegetables clean and crisp, cook lightly, then plunge into iced
water (the vegetables, that is). - manual for a Russell Hobbs electric steamer