I have used my phone only once and since that time it seems to be in constant "phone off-hook" mode. The screen never shows any information. I must remove it in order that my other phones operate. When I reconnect it I get a dialtone on the speaker and the "Hands-free" light illuminates. After a few seconds I get a recorded message to hang up after which the "Hang up alarm signal" sounds. How can I get the phone to operate properly?
Check that the hookswitch is operating properly. With the handset out of the cradle, push the hookswitch down, it should give some resistance then pop back up after you release it. Possibly it is not popping back up fully, therefore it is seizing the line always. Most switchhooks have a spring connected to them inside the phone to allow them to operate properly, if the spring is damaged it could cause the problem you've described.
Answers & Comments
Check that the hookswitch is operating properly. With the handset out of the cradle, push the hookswitch down, it should give some resistance then pop back up after you release it. Possibly it is not popping back up fully, therefore it is seizing the line always. Most switchhooks have a spring connected to them inside the phone to allow them to operate properly, if the spring is damaged it could cause the problem you've described.