Line in Use Message

[JS722]

Nearly every day, for serveral hours, my home phone line is unusable. I have a "line in use" message on the phone. When this happens I cannot make or receive calls on my phone. I still have a dial tone but, if I try to make a call, I hear beeping noises that sound similar to a fax machine. The problem eventually clears itself after several hours.

If I Google "Verizon Line In Use" I see that I am not alone in having this problem. Any ideas on possible causes?

[LawrenceC]

If you are having an issue with your Verizon service, you can use the Verizon Troubleshooter to fix and report issues with your Verizon Phone, Fios TV, or Internet Service, as well as to schedule a repair, here is the link:
http://www.verizon.com/repair
You can find tools on the Verizon Residential Support page that may help you diagnose your issue:
http://www22.verizon.com/residentialhelp

[andyc3]

I just converted my security system's phone connection from landline to wireless. The installation tech fogot to disconnect the obsolete landline RJ-11 connector. As a result the landline was "seeing" use from the wireless line and reported the connection as busy. Solution: disconnect the RJ-11 connector from the landline connector jack inside of the security device panel. 

The general advice to resolve  "Line in Use" issues is to look for other connections in the house. That is good advice, but interfering connections may be made through telephone jacks in unexpected places serving non-typical telephone line uses.

[NewFiosCustome1 · Accepted solution]

After getting Fios, we kept getting the message “Line in Use”.  We could not make or receive calls.  We would contact Fios and they would work their magic and the phone would start working again, but the problem would reappear.  

Then we started getting an error code with our Security system.  Finally it was discovered that our ADT security system was trying to make contact with their system (Line in Use) with no avail.  The ADT technician had to upgrade our security system and remove it from the phone line.  Haven’t had any more problems.  I hope this information helps someone else.