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Connection Manager errors (or DUN errors) display when there are problems connecting to the T-Mobile network. Learn how to address these errors below.

 

Error codes or messages you may encounter in Connection Manager and the steps to resolve them
Error code / error message Resolution steps
619, 628 'The port was/is disconnected'

This error is happens when your account is suspended or if you have low signal.

To resolve this error, restart your computer and try to connect. If you have no signal or only 1 bar, try moving location to another room or closer to a window. If the above steps do not resolve your issue, contact us.

650, 651, 652

'The Remote Access server is not responding'

'Your modem has reported an error'

'Unrecognized response from the device'

  • Your computer has an active connection in the Mobile Broadband API (Windows 7)
  • Network issue or outage

To resolve this error, follow these steps:

  1. Restart your computer.
  2. When you log in to the operating system, open the connection manager.
  3. For Windows 7, disconnect any active connections in the Mobile Broadband API.
  4. Attempt to connect to Mobile Internet.
  5. Uninstall the connection manager software.
  6. Install the connection manager software.
  7. Restart your computer.
  8. When you log in to the operating system, open the connection manager and connect.
  9. If the above steps do not resolve your issue, contact us.

'Connecting/Connection disabled'

This error happens when you're not in T-Mobile coverage, signal is too low, or your computer does not meet the minimum system requirements.

To resolve this error, follow these steps:

  1. Make sure your current location is within T-Mobile coverage. and connection manage is showing at least 2 bars of signal.
  2. Check your computer and make sure it meets the system requirements.
    Note: System requirements are found in the Start Guide.
  3. Restart your computer and try to connect to Mobile Internet. If you have no signal or only 1 bar, try moving location to another room or closer to a window.
  4. If the above steps do not resolve your issue, contact us.
'Multiple connections are not allowed'

Causes:

  • Your computer is currently connected to another network.
  • Your computer has an active connection in the Mobile Broadband API (Windows 7)

To resolve this issue, follow these steps:

  1. Disconnect from any active Wi-Fi networks.
  2. For Windows 7, disconnect any active connections in the Mobile Broadband API.
  3. In the connection manager, attempt to connect to Mobile Internet.
  4. Restart your computer.
  5. When you log in to the operating system, open the connection manager.
  6. Attempt to connect to Mobile Internet.
  7. If the above steps do not resolve your issue, contact us.
'No SIM Found'

This error is specific to the Rocket 4G and happens if your SIM card is not properly inserted in the USB laptop stick, or if the laptop stick doesn't recognize the SIM card. This can also happen if there is a problem with the Connection Manager.

To resolve this issue, follow these steps:

  1. Check your computer and make sure it meets the system requirements.
    Note: You can find the system requirements for your device in the Start Guide.
  2. Unplug your laptop stick
  3. Remove your SIM card.
  4. Reinsert your SIM card
  5. Restart your computer.
  6. Insert your laptop stick directly into a USB port on the computer.
  7. When you log in to the operating system, open the Connection Manager.
  8. Attempt to connect to Mobile Internet.
  9. If the above steps do not resolve your issue, contact us.
'Checking Device'

This error is specific to the Rocket 4G and happens if your computer does not meet the system requirements or if your computer does not recognize the modem. It can also happen if you're using a docking station or USB, or if your computer is turning off USB devices to save power.

To resolve this issue, follow these steps:

  1. Check your computer and make sure it meets the system requirements.
    Note: You can find the system requirements for your device in the Start Guide.
  2. Insert your laptop stick directly into a USB port on the computer.
  3. Restart your computer.
  4. Confirm the laptop computer is connected to the power adapter, and the power adapter is connected to a wall electrical outlet.
  5. When you log in to the operating system, open the Connection Manager.
  6. Attempt to connect to Mobile Internet.
  7. Uninstall the Connection Manager.
  8. Reinstall the Connection Manager
  9. Restart your computer.
  10. When you log in to the operating system, open the Connection Manager.
  11. Attempt to connect to Mobile Internet.
  12. If the above steps do not resolve your issue, contact us.

"Searching For Wireless Device"

"No Wireless Device"

"No network available" (Mac OS X)

Causes:

  • Your computer does not meet the minimum system requirements
  • You have the laptop stick in a USB hub or in a laptop docking station
  • Your computer is turning off USB devices to save power
  • Your computer does not recognize the modem

To resolve this issue, follow these steps:

  1. Check your computer and make sure it meets the system requirements.
    Note: You can find the system requirements for your device in the Start Guide.
  2. Insert your laptop stick directly into a USB port on the computer.
    Note: This does not apply for netbooks or notebooks with a SIM card slot.
  3. Restart your computer.
  4. Confirm the laptop computer is connected to the power adapter, and the power adapter is connected to a wall electrical outlet.
  5. When you log in to the operating system, open the connection manager.
  6. Attempt to connect to Mobile Internet.
  7. Reinstall the webConnect Manager.
  8. If the above steps do not resolve your issue, contact us.
'phoneserver.exe has stopped working'

This error is specific to the Rocket 4G and happens because of the following:

  • Temporary problem with the Connection Manager
  • Corrupted file in the Connection Manager

To resolve this issue, follow these steps:

  1. Restart your computer.
  2. When you log in to the operating system, open the Connection Manager.
  3. Attempt to connect.
  4. Uninstall the Connection Manager.
  5. Reinstall the Connection Manager.
  6. Restart your computer.
  7. When you log in to the operating system, open the Connection Manager.
  8. Attempt to connect.
  9. If the above steps do not resolve your issue, contact us.

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