There are many points at which a telephone line may be disconnected, and the complexity of reconnecting the line depends on where service was interrupted. Some users experience service interruptions when a line inside the home or business is disconnected from the jack, and that situation is an easy fix. Outside wiring, or contacting the telephone carrier for service issues, though, can be somewhat more daunting of a task.
Frst pick up your phone and find the flat, usually grey, beige or black wire connected to the back of the phone. The wire should be connected to your telephone via a plastic modular plug that is firmly seated in a port in your phone (the port is usually marked "Line"). Ensure that the line is plugged firmly into the phone and then follow the wire to its other end.
Verify that the wire is firmly connected to the jack. The other end of the phone wire should terminate in a plastic modular (RJ-11) plug identical to the one plugged into your telephone. If this end of the wire has become loose or disconnected, plug it back into the telephone jack on the wall, or back into the "Phone" port of your modem or fax machine. If the modular plastic plug is damaged, or if it does not fit correctly into the jack, it may need to be replaced (a replacement line can be inexpensively obtained at any retail store).
If your phone is plugged into a modem or fax machine, repeat the process. If the wire coming out of your telephone terminates at a modem or fax machine, a separate but similar wire must connect the modem or fax machine to the telephone jack at the wall.
Access your phone jack. Modular jacks simply snap apart, so firmly grip the jack's housing and pull it from the wall (note: if you observe a screw holding your jack together, you may need to remove this screw to complete this step).
Check the jack. Inside the jack there should be four wires, a red, green, yellow and black. Your telephone line uses the red and green wire, so ensure these wires are firmly connected and held in place by screws. If they are not, or if they appear broken, you will need to wire a new jack (consult a separate eHow article on "How to Wire a Telephone Jack"). If the red and green wires are firmly secured and held in place, snap (or screw) your jack back together to restore it's position on the wall.
Check inside/outside wiring. Your telephone jack is physically connected to the telephone company's Network Interface Device (NID) by wires. You may see a single, thick wire coming out of your telephone jack and going into your wall or floor. You will need to follow this wire to ensure it is not broken, kinked or otherwise interrupted between the jack and the NID.
Go all the way to the NID. Follow this wire, if possible all the way from the jack to the grey (and usually locked) box on the outside of your home or business (if you are in a multifamily or multi-office building, this box may be located in a common hallway or basement). Since your telephone service depends on this wire being intact and uninterrupted, follow the wire all the way to the NID while checking for kinks, exposed copper or breakage. Once you reach the NID, stop and proceed to section three of this article. The NID is telephone company property and consumers are generally not authorised to open it.
If your telephone wiring appears to be intact both within the jack and inside/outside your premise, you will want to contact your telephone service provide for additional assistance. In most locations, you can dial "6-1-1" from any landline telephone (including payphones) to reach your local telephone company. In some rural locations or areas served by smaller carriers, though, you may need to look up your telephone company's listing in your local phone book.
Ask for someone in "Repair." When you contact your local telephone company, you will likely be greeted by an Integrated Voice Response (IVR) menu. If such a device answers the phone and presents several options from which to select, choose the option for "Repair." Your call should be automatically directed to the appropriate department. If you reach a human instead of an IVR, simply ask to speak with someone in the repair department.
Report your trouble and check for billing issues. When you reach your telephone service provider's repair department, report that your telephone line appears to be disconnected and that it is out of service. The repair technician will ask you some basic troubleshooting steps (which you have already completed in sections one and two of this document), then set up a time to dispatch a technician. Because you have already verified the wiring inside your premise, you should not need to be present when the technician arrives. If you do not have a billing issue and all of your payments have been credited to your telephone account, you will not need to speak with anyone else and your line will be reconnected as soon as the telephone company completes their troubleshooting. In some cases, though, your repair agent will tell you that your line has been disconnected due to a payment issue. If this situation occurs, the agent may transfer you to speak with someone in the "Collections" department.