Microsoft KB Archive/324466

= BUG: ActiveSync Does Not Successfully Connect Through Direct RS232 Serial Cable =

Article ID: 324466

Article Last Modified on 7/27/2004

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APPLIES TO


 * Microsoft Pocket PC 2002 Software Standard Edition

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This article was previously published under Q324466



SYMPTOMS
When you use an RS232 serial port to connect Pocket PC 2002 to your desktop computer, the connection may not succeed in connecting after trying for about 4 seconds.



CAUSE
This is caused by a bug in the automatic baud rate seek logic of the Pocket PC 2002 operating system. This bug causes the device to abort the connection attempt before the Desktop ActiveSync component has determined the communication speed and reconfigured itself.

This is a problem only if the ActiveSync communications settings for your device are different from the ActiveSync communications settings for your desktop computer.



WORKAROUND
The desktop ActiveSync component can typically detect the device settings. However, it does not respond at the correct communications rate before the device aborts. When you try to connect a second time, the problem generally does not recur.

An alternative workaround is to set the ActiveSync baud rate on the desktop to use the same baud as the device. You can set the baud rate by editing the registry on the desktop host computer, as detailed in the steps that follow.

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

 On the desktop computer, click Start, and then click Run. Type regedit, and then press ENTER. Locate and go to the following registry key: 

 Change the SerialNoAutoBaud value to 1 . Change the SerialBaudRate to a number that matches the baud that you select in ActiveSync on the Pocket PC 2002 device, including any other devices that you want to connect.

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STATUS
Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

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MORE INFORMATION
If you synchronize more than one device with any one computer by using a serial port, you may experience this problem frequently. To avoid this, make sure that all devices are trying to connect using the same communications settings.

On Pocket PC 2002, to change the communications settings from the ActiveSync application, follow these steps:
 * 1) Start ActiveSync.
 * 2) On the Tools menu, click Options.
 * 3) On the PC tab, under Enable synchronization when cradled using, select a baud rate from the list.

Note the following about working with synchronization settings:
 * You do not experience this problem if you use USB hardware. The option USB requires different hardware from the other options.
 * If you select a higher data rate, your synchronization occurs faster. However, many older desktop systems cannot reliably communicate at the higher speeds.
 * After you change the communications rate, you may have to make multiple connection attempts. This is because the Desktop ActiveSync determines the connection speed dynamically.
 * Consider that if you change the registry for ActiveSync to try only one baud rate, the device cannot connect unless the device baud rate matches.

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