Ah, thanks for the reminder...
Michael sent me his image file, and i received it and could look at it on my old Android phone back in January.
Now i'm back home, so i looked into my accumulated email, and there it was.
I've just now extracted it to my Win 10 laptop, and herewith shall attempt to post it:
... no problems.
Instead of a PNG, the file that arrived in the mail had the JPG extension.
Back in January i looked at the raw data bytes in the file (on my phone), and it had proper jpg internal flags.
The forum's upload dialog had no problems with it just now.
(running Google Chrome as my browser under Window 10)
In an Apple, there may be "metadata" in a separate file that may be getting in the way, but that didn't arrive in the email attachment.
So why it didn't work for him back in January i cannot say.
You are certainly welcome to send me any problem picture ( rseymour (at) wolfenet.com ) and i'll look at it and attempt to add it to this thread.
You mentioned that you could "fix" the issue by emailing the file to yourself, so i fear that the email packing process is intelligently shaving off the icky bits.
If you have a program like StuffIt or Zip (preferred..and StuffIt can Zip) that could perhaps package the image file *before* the email packer gets its fingers on it, that might help convey the icky bits to me.
--dick