I think what he is getting at is that the 1600 series phones upgrade via HTTP and the 5600 series phones upgrade via TFTP. If you are using the IP Office and a Compact Flash card internally to upgrade your phones then both the HTTP and TFTP server IP addresses in Manager should point to the IP Office. If you are using an external TFTP server such as Manager you should leave the HTTP server IP blank and point the TFTP server to the IP of the PC running Manager (or whatever you are using). The phones should then point to the IP Office which will proxy the HTTP request from the 1600 phones as TFTP requests to Manager.
If you enter an HTTP address in the IP Office then you must be running a HTTP server to service those phones as the IP Office will not proxy HTTP to TFTP requests if the HTTP address is not blank.
Kyle Holladay
ACA-I, ACA Call Center, ACS-I, ACS-M, TIA-CTP, MCP/MCTS Exchange 2007
ACE Implement: IP Office
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