If you receive the message "The computer's modem is being blocked from connecting (AC-1000)" while signing on to the AOL® service, try the solutions listed below. After trying the first solution, check whether the issue is resolved. If you still receive the message, continue using the suggested solutions until the problem is fixed.

You may wish to print or save a copy of these instructions as this page may not remain visible as you go through the suggested steps.

Information you need

You will need to know the version of the Microsoft® Windows® operating system installed on your computer. You can find this information by following the steps given in the online help article Determining your version of Microsoft Windows

You will also need to know the version of AOL Connectivity Service (ACS) installed on your computer before attempting the solutions given below. If you are using AOL 9.0 VR or higher, you have ACS 4 installed on your computer. If you are using AOL® 9.0 Optimized, AOL 9.0 Optimized SE/LE, or AOL Security Edition, follow the instructions given in the online help article How do I determine the version of AOL Connectivity Service (ACS) I have?


Select the correct location

1. Launch the AOL software, but do not sign on.


2. Click the Connection drop-down menu, and then click the location specific to your connection method.

Note: For dial-up connections, the default location is Home. All broadband connection methods use Broadband as the default.

Restart your computer and try again

Note: You may want to print this article before proceeding with this solution.

If you haven't recently restarted your computer or you don't restart your computer very often, we recommend that you restart your computer. This helps clear the internal memory (RAM), which often resolves many issues.

Check physical connections

1. Check whether the phone cord is unplugged from the back of the computer or wall jack.

2. Plug a telephone cord into the phone jack used by the modem, and then pick up the receiver to check for the dial tone. If there is no dial tone, please contact your local phone company.

3. Ensure that the phone line goes directly from the wall jack to the computer. Disconnect any splitters or answering machines that are connected to the phone line to ensure that these devices are not causing the issue.

4. Ensure that one end of the phone cord is plugged into the wall jack and the other end is plugged into the modem jack. The modem jack will either be labeled Line or be represented by a phone receiver.

5. If you are using an external modem, ensure that the power cord is plugged into a working wall jack.

6. Ensure that another member of the household is not using the home phone line.

Check the modem using the Windows dialer

While troubleshooting connectivity issues, it is important to ensure that the modem is working properly. If the modem does not generate any output, you will need to contact the manufacturer of the modem for further assistance. The instructions to check the modem using the Windows dialer may differ depending on the version of Windows installed on your computer. Please check our help article Check the modem using the Windows dialer and click on your version of Windows.

Enable only essential startup programs

Multiple programs may have been set to start automatically when a computer is turned on. These programs may cause the computer to slow down. Not all startup programs are essential for the proper functioning of your computer. For instructions to enable only the essential startup programs on your computer, please click the appropriate link from the ones given below, depending on the version of Windows installed on your computer.

If you are using Windows 2000/Me/98, you will have to manually close all the programs that are currently running on your computer to resolve the issue. Please click the link corresponding to the version of Windows you have on your computer for instructions to close all programs.

Delete all connection locations and redetect the modem

Completely deleting the sign on locations and connectivity files removes not only bad access phone numbers but also dialing options and incorrect modem or broadband settings. The AOL software will automatically search for and select the right connection device and guide you through the process of selecting appropriate access phone numbers and dialing options.

WARNING: You will incur charges on your phone bill if you select an AOL access phone number that is a long-distance call or is not covered by your local calling plan. Please check with your local phone company to determine whether the access phone numbers that you select are local for your calling plan. Remember that members on certain plans may be charged an hourly rate for dial-up connections. See AOL Keyword: My Account or go to http://myaccount.aol.com for details regarding the charges applicable to your account.

Please click the link corresponding to the version of ACS on your computer for instructions to delete the connection locations and redetect the modem.

Uninstall and reinstall the AOL software

If the issue persists, we recommend that you uninstall and reinstall the AOL software. Uninstalling the AOL software removes all damaged and non-repairable files. Once the uninstallation is complete, reinstalling a new copy of the AOL software is quick and easy. Please note that uninstalling the AOL software removes all screen names and settings associated with it. However, your Filing Cabinet files will automatically be stored on the desktop in a folder named Saved on AOL.

Important: If you have saved your AOL password on the AOL software, ensure that you remember your password before you uninstall the AOL software because uninstalling the software will delete your saved password. If you don’t remember your password, we recommend that you change your password before proceeding any further. You will also need to remember the answer to your Account Security Question (ASQ) to be able to change your password. You can change your ASQ if you don’t remember the answer to it. For instructions on how to change your password or ASQ, refer to the following online help articles:

Please click the link corresponding to the version of Windows on your computer for instructions to uninstall the AOL software.

Note: If you are unable to uninstall the AOL software, refer to our online help article Can't uninstall the AOL Desktop Software.

Contact your computer manufacturer

We have determined that the issue is not caused by the AOL software. We recommend that you contact your computer manufacturer, or if your computer is no longer under warranty, a local computer repair shop or technician, for further assistance. Let the computer manufacturer/technician know about the issue. AOL uses many programs to deliver content to your computer, and these programs should function efficiently. All software programs are highly dependent on the computer's operating system and other applications to work properly. It appears that one of the following programs/applications may be the cause of the issue.

  • The computer operating system
  • Several media players
  • Many text editors and text viewers
  • Microsoft Internet Explorer and other Web browsers