Working on a project to bring a batch of Cisco 7960G phones online with a newer 7.1 CUCM server. The issue is that the phones were donated, and although new in the box they were using just about every firmware version from 3.x to 8.x, SCCP and SIP. The newer revisions were simple enough to manually upgrade via TFTP, but the 3.x revisions absolutely would not upgrade. We tried upgrading from 3.x to 5.x, 7.x, etc with no luck. We would have liked to upgrade them from 3.1 to a newer 3.x revision, but all of those files from Cisco are packaged in an exe intended for CME. This limited our options. Finally found an obscure way to get around the UAL conflicts.
Workaround upgrade from 3.x to 7.x SIP then back to SCCP. Read More