AAA

No, this is wrong. ICS can't decode this message correctly. Can you see IMG_123.jpg image?

As I wrote TMimeDecode.ProcessLineBase64  can skip trailing spaces and does this.

If you remove trailing spaces file be "more" valid and can be processed by online validators/email programs.

But still can't be decoded by TMimeDecode.

TMimeDecode.ProcessLineBase64 even can skip trailing spaces but...

Can be length a problem?

May be problem is length not "multiple of four" as noted in TMimeDecode.ProcessLineBase64?

1. Base64 decoder fails. See attached file. File from the wild, not is test-created.

2. When attached file is quoted-printable encoded and file is plain text then decoder adds unwonted CRLF.

3. When attached filename not have quotes then decoder lower case filename:

...

  filename=IMG2345.jpg

Will be img2345.jpg

I think you can recreate 2 and 3. But 1st bug is real bad.

[I removed the file]