I don't know for sure why the address is rejecting - don.gayle@verizon.net is the appropriate e-mail address. One possibility is that the photo you are trying to send has too many pixils (too much memory) for transmission by either your provider or mine. I do have e-photos of 3 relatives in Co E and one in the 4th LA Cavalry (McNeill's), including the original of one taken of my GGGrandfather and his twin brother (Jonathan and David Rogers of Co E, 2nd LC) in 1860 or 1861.
Hopefully you can get the tintype e-copy through as I would really like to see it. Identifying an anonymous photo is an issue as you know, because approximately 2300 men served in the 2nd LA Cavalry and possibly 90,000 from Louisiana as a whole.
Thanks for your very kind efforts to share a view of the tintype.
Don