I have a signature I've been using for years that has never given me issues with anything (except plain text that doesn't allow any font changes of course) but when I created a new signature with different color combinations, it does not show in certain internal email messages that are defaulted to "rich text" when replying.
This is where it gets weird, the signature that does work - if I go into the signature option to change the font color, it won't change; almost like it locked itself to this setting. That signature still has NO issues if I select that one for these emails. HELP!