Customer's will start a published application or desktop and at random intervals the Viewer application will close with no errors or messages.


This article is intended for Citrix administrators and technical teams only. Non-admin users must contact their company’s Help Desk/IT support team and can refer to CTX297149 for more information.
 

Fixed in the latest release.
Upgrade to Citrix Workspace app for Macintosh version 21.04.

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Problem Cause

* There is a function `SCVD_QueryAndDispatchC2HCommand` that sends smartcard commands from the client to the server, this is run on the `Winstation Driver Dispatch Queue` thread. 
* There is another function `SCVD_DispatchH2CCommand` that sends smartcard commands from the server to the client, this is run on `legacyVCRecvQueue` thread. 
* Both these functions write to the same `PSCVD_INSTANCE` structure that represents the smartcard, and this structure is not thread safe. 
* These threads run in parallel, and synchronization issues between them was corrupting the data stored in this structure, forcing us to withhold packets and causing disconnections. 

At random times the Workspace app for Mac Viewer application closes with no error or message.