I have an issue about a Cisco Unified CallManager 188.8.131.520-11. When updating any information of a device (a phone 7911) and then clicking in "Save" I receive a message box with the following text: "Operation Completes By Date/time must be greater than current date/time".
The same occurs when updating others parameters of many devices (phones, in general).
If any person is already faced this problem, please, help me in solve it.
I had the same problem and I resolved by changing the Certification Authority Proxy Function (CAPF) Information in the phone configuration page, by selecting No pending Operation instate of Install/Upgrade