PVSS00event - SYS/SEVERE - The attribute does not exist in this config "DPE-ID":_alert_hdl.._ack_state

When acknowledging alerts the following message can occur, the information is written to the PVSS_II.log-file.

PVSS00event (0), 2010.09.05 10:32:28.204, SYS, SEVERE, 19, The attribute does not exist in this config, DP: System1:Pump1.state.off:_alert_hdl.._ack_state, MAN: (SYS: 1 Ui -num 3 CONN: 1(R)), USER: 3072

Log-message with symbolic names:

PVSS00event (0), <TIMESTAMP>, SYS, SEVERE, 19, The attribute does not exist in this config, DP: <DP-element>:_alert_hdl.._ack_state, MAN: (SYS: <system-number <manager-type + number>), USER: <user-ID>

In older versions the log-message can have a different type/priority:
PVSS00event (0), 2010.09.05 10:32:28.204, PARAM,WARNING, 19, The attribute does not exist in this config, DP: System1:Pump1.state.off:_alert_hdl.._ack_state, MAN: (SYS: 1 Ui -num 3 CONN: 1(R)), USER: 3072

Log-message with symbolic names:

PVSS00event (0), <TIMESTAMP>, PARAM,WARNING, 19, The attribute does not exist in this config, DP: <DP-element>:_alert_hdl.._ack_state, MAN: (SYS: <system-number <manager-type + number>), USER: <user-ID>

This message occurs when you try to acknowledge an alert which needs to be single-acknowledged with common-confirmation.
The alert remains unacknowledged.