Hi,
Can you please confirm the below ?
1. Are you upgrading the firmware for the phones (6945) from version 9-1-1-0 ?
2. What firmware version are you upgrading to ?
3. Are these CME registered phones ? If so what is CME version ?
4. Are these CUCM registered phones ? If so what is CUCM version ?
Can you please post the configuration that was used as procedure to upgrade the firmware ?
Below is CME resource link, guide line for upgrade/downgrade the SCCP firmware:
http://www.cisco.com/en/US/docs/voice_ip_comm/cucme/admin/configuration/guide/cmeinstl.html#wp1070512
Once you confirm the versions, i will be able to give you more information on the same ?
Regards
Prashanthi Velpula