Dialup networking using operator assist option not working on Windows 7

Question

I know how to enable operator assist in Windows 7.  The issue is that when I click the initial Dial button I get a dialogue box stating modems connecting, I see the modem initialize but the connecting dialogue box never changes to
the second dialogue box that tells you to manually dial your number and hit connect when you hear the carrier from the far end modem.  I have tried different laptops running windows 7 and none of them work.  One has a built in soft modem, one has
a USB serial port connected to an external 3Com Courier modem and one has a USB modem.  Everything works on Windows XP, but none of the Windows 7 machines work.  I have tried this using Windows 7 Enterprise edition, and Professional edition.  If
I wait long enough I eventually get the 638 time out error but the modems connecting dialogue is still on the screen.  If I hit the cancel button it just cancels the operation and if I dial the number and hear the far end carrier I can't get my modem
to answer.  I have looked at the modem log file from both a working windows XP and a Windows 7 system and they are both exactly the same up to the point of the modems connecting dialogue box, the Windows XP log shows a Dial command
when I connect using the second dialogue box.
Thanks in advance...
Randy

Answer 1

Hi,
Here are the details of the expected behavior (as observed by XP SP3 behavior):
1. Both source and target modems are serial devices.
2. Network Connections is opened
3. Advanced menu -> Operator-Assisted Dialing is selected (enabled)
4. Dialup connection is double-clicked and dialog to connect appears
5. Dial button is clicked
6. Dialog appears: " Pick up the handset and dial (or ask the operator to dial). Press OK immediately after dialing, then replace the handset."
7. Customer picks up handset connected to line port of modem and dials live operator, operator picks up and forwards call to specified target modem
8. As soon as customer hears target modem tone he hangs up handset and clicks OK on dialog from step 8.
9. Dialog appears: "Modems connecting..."
9. Modems connect
Here is the observed behavior in Win7:
1. Both source and target modems are serial devices.
2. Network Connections is opened
3. Alt key pressed which brings up menu bar. Advanced menu -> Operator-Assisted Dialing is selected (enabled)
4. Dialup connection is double-clicked and dialog to connect appears
5. Dial button is clicked
6. No dialog to pickup handset ever appears. Instead we see dialog for "Modems connecting..."
7. Modems can't actually connect because no number was ever dialed. Opportunity to dial number to live operator is not presented to user.
This performance is by-design. The dialog box is not appearing because the service is running in session 0. Generally, user sessions are from session 1. Since the service is running in session 0, the dialog box wont be visible in other sessions(user sessions).
This session 0 isolation was implemented right from vista.. In XP, service is running in user session and hence user is not experiencing any problems.
Since this function is old and we won't fix it in Windows 7. But we could provide the workaround as below:
Resolution
1. Start->Run
   services.msc
2. Start the “Interactive Services Detection” service if not already started.
3. Right-click this service and select Properties
4. Select Log On tab and enable “Allow service to interact with desktop”.  Click OK to accept the changes.
5. Repeat step 4 for the Telephony service
6. Make the OA call:
a. Click Dial on DUN dialog
b. Dialog appears, select “View the Message”
c. Session switched by system – “Manual Dial” dialog appears
d. Pick up handset and dial far-end modem, wait for far-end modem tone, click OK and hang up handset
e. Click “Return now” – system switches session back to user session.
f. Modems should connect.
Best Regards,
Annie Gu