We have a number of 509s that were running 7.5.2 when purchased and worked fine. Our provisioning server was mistakenly configured to hand out 7.1.3 to all the phones.
Now that the phones are running 7.1.3 we are unable to move them to a newer FW version. I found the article detailing that devices need to move to 7.5.2 before being upgraded to anything newer but can't find any other documentation for this older FW and the correct upgrade path to bring them current. Ideas?