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Article ID: 2021760 - Last Review: March 23, 2010 - Revision: 1.0


If a device is already claimed by an application, attempts to claim that device by applications running from different user accounts fail. POS for .NET returns an Argument exception instead of a POS exception. Once a user account receives this failure, subsequent attempts by that user account to claim the device fail, even after the device is released.

This failure does not occur for two applications running from the same user account. Access to the global event is denied only for different accounts. 


POS for .NET uses global events for tracking when a service object claims a device.  This only applies to service objects that leverage the NamedEvent class.  Basic and Base classes leverage this – although service objects based on the Basic class may choose to provide their own implementation.


The fix enables multiple user account usage of a global event, by providing a security attribute when the global event is created.  In the event of a failure, the proper claim logic and exception results are now returned.
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use ( for other considerations.

  • Microsoft POS for .NET
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