The phone's message indicator should glow red for a few seconds. The phone begins its software loading process. After a short delay, the phone displays Initializing and then Loading. The loading phase may take a few minutes.

• If the phone has an existing software boot file (ie. it has been previously installed), it loads that file and then display Starting.

The phone displays DHCP and a timer as it attempts to request an IP address and other information from a DHCP server.

After a few seconds, DHCP negotiation is completed. If the timer reaches more than 60 seconds, it indicates an error in either the network or DHCP server configuration.

Once DHCP has completed successfully, the phone will request files from the file server indicated in the DHCP response. The first file requested details the other files that the phone should also load. The phone makes its file request using HTTPS. If this fails it makes the same request using HTTP. If that fails it makes a final request using TFTP. If all requests for a file fail, the phone fallbacks to using the current version of the file it has in its own memory.

The phone goes through a cycle of requesting files, loading files and then transferring the files into its flash memory.

Following file loading, the phone displays Ext. =. See Registering phone.