I used to see this error constantly with some of our users who used Verizon Access Manager, and ANY type of Air Card; PC5750, PC5740, PC5220, tethering with Blackberries, etc. Using the VZAM software, or US Cellular sometimes you will not get an error, sometimes you will. The best way to test what error you are getting is to insert your air card, and use the Dial Up connection that is created by the software to attempt to connect (in Networks Connections). You will always get some sort of error. So far I have not seen this on Windows 7, only on Windows XP PRO SP2, or SP3, so I will write this up assuming you have Windows XP.
CAUSE: This issue may occur if the TCP/IP protocol has become unbound from the dial-up adapter, or if a conflict is created when a second WAN Miniport IP device driver loads. Back to the top Back to the top
RESOLUTION: To resolve this issue, uninstall the WAN Miniport IP and PPTP devices. To do so, follow these steps:
To be safe, uninstall the CISCO VPN (if you use it). You should also remove the BB, or Aircard from device manager.
Step 1:
1. Open Device Manager
2. Under the View menu click Show hidden devices.
3. Under Network adapters, you will see WAN Miniport IP devices. If a WAN Miniport IP device is listed, continue to the following step. If no WAN Miniport IP devices are listed, go directly to step 16.
4. Click Start, click Run, type regedit in the Open box, and then click OK.
5. Locate the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}
6. On the Registry menu, click Export Registry File, type backup-key in the File name box, and then click Save. (Note You can restore the changes that you make to this registry key. To do so, double-click the backup-key.reg file that you saved.)
7. Click each of the registry subkeys under this key, and then view the Data column of the DriverDesc value to determine which of the subkeys corresponds to WAN Miniport (IP). For example, the 0005 subkey.
8. Right-click the subkey whose DriverDesc value data is WAN Miniport (IP) or WAN Minport (PPTP); (for example, right-click 0005), and then click Delete. Click Yes to confirm that you want to delete the key.
9. Quit regedit
10. Open Device Manager
11. On the View menu, click Show hidden devices.
12. Under Network adapters, uninstall the WAN Miniport (IP) and the WAN Miniport (PPTP).
Step 2: Reinstall the WAN Miniports
1. Find netrasa.inf in c:\windows\inf
2. Make a copy of the file and name it netrasa.inf.save
3. Open the original copy of netrasa.inf
4. Under the [ControlFlags] section: place a semicolon in front of the line that starts with Excludefromselect=\
5. Continue to add semicolons to all the lines beneath until coming to the line: MS_NdisWanNbfIn,MS_NdisWanNbfOut
Step 3:
1. Start the Add New Hardware wizard from the Control Panel
2. Select the hardware is already installed.
3. Select “Add a new hardware device” from the end of the list.
4. Select Install the hardware that I manually select from a list. (Advanced)
5. Select “Network Adapters” followed by “Microsoft” and then both the PPTP and the IP Wan miniport one at a time. (NO need to reboot between these steps)
6. Reboot after running through the wizard for both the PPTP and IP miniport.
7. Select Start -> Run and type: netsh int ip reset c:\resetlog.txt
(For details, see KB299357)
8. Reboot and try your connection. This worked for me and has worked for others.
Hopefully this helps some people, Verizon has no idea what’s going on, so I had to find this on my own.
update July 26th 2010 : This also fixes the US Cellular’s error 720 with a UM175, or 185.