Just for kicks, try this. The C2950 switch can act as a tftp server for other switches, so as a troubleshooting method select a switch (already updated) that is directly connected to the switch having trouble and configure it to act as a tftp server going to global configuration mode and type "tftp-server flash:c2950-i6q4l2-mz.121-22.EA7.bin". Then go to the problem switch and attempt the tftp download from the eighbor switch.
If the download is good, repeat with a switch closer to the tftp server to check the path, if not then repeat with a neighboring switch on another port to attempt isolation of the problem to a particular port.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...