I repeated get this error when trying to use the links to CUCM admin pages. Is there any support during the sandbox sessions?
For the cucm admin page access issue the solution is to create and install a trusted SSL certificate so that users who access https://<node>/ccmuser do not receive a certificate error.
But in case of Sandbox On a running reservation select the device and then on the right hand side of the screen click 'Show Attributes' to see the details and try.
Reference - https://communities.cisco.com/message/157606
Thanks and Regards,
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