SOLVED: CISCO 8845 cannot download xml from my tftp server

[cainram]

The problem was with case sensitivity of the files... Everything is working as it should. Thanks to everyone that took a look

I have a TFTP server running on my FusionPBX server (Debian based). It generates SEP{mac}.cnf.xml files for configuration. If I put the files in another, known working, TFTP server, the phone can download the file and register. So I know the phones work and I know the XML file is good. Here is what I'm experiencing:

I CAN use the terminal TFTP client on an Ubuntu machine on my local network to download files from the Debian TFTP server.
I cannot download files using TFTP client (command line) on my Windows machine.
I CAN download files using TFTPd64 GUI on another Windows machine
I cannot get my Cisco phone to provision via TFTP with the FusionPBX Debian server. Same phone has no issues with other TFTP servers. <--This is my major concern.

The server is on a public IP. Here is the xinetd/tftp config:

service tftp
{
protocol = udp
port = 69
socket_type = dgram
wait = yes
user = nobody
server = /usr/sbin/in.tftpd
server_args = -s /tftpdata
disable = no
}

It is frustrating because some clients work and some don't. And the only one I really care about (the phone) doesn't.

Thanks in advance for any help or ideas

[cainram]

Update: Turns out the issues I was having with the Windows machines was due to the firewall settings in the Windows machines themselves. So - I can now download from the server from everything I have thrown at it EXCEPT the phones. I have also added a rule to my server's firewall to allow all traffic from my office's IP address (where the phone is).

What am I missing!?!?

Thanks in advance