Problem:
Connecting to XenDesktop get the following error:
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Desktop Viewer
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The connection to "Desktop-NAME" failed
with status (1110).
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OK
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When you bypass the Citrix NetScaler and connect to StoreFront server it works, possible cause is recent upgrade of NetScaler.
Solution:
Upgrade Citrix Receiver to 4.3 or higher older versions drop support for weaker ciphers and protocols.