3268405 - RFC Connection Error in step Check Configuration of Managed Systems Configuration in SAP Solution Manager 7.2

The following error occurs in Step Check Configuration of SAP Solution Manager Managed Systems Configuration:
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Error:
Check has not been executed due to communication failure: Error when opening an RFC connection (CPIC-CALL: 'ThSAPOCMINIT', communication rc: CM_RESOURCE_FAILURE_NO_RETRY (cmRc).

Action:    
Check that the WEBADMIN destination can be reached and that the SAPSolution Manager maintenance mode is turned off.To check the Solution Manager system internal connectivity, starttransaction SM59. Expand the section “TCP/IP connections” and checkwhether the WEBADMIN RFC connection exists. Perform a connection testfor this RFC destination. If this connection is broken or does notexist, please start transaction SOLMAN_SETUP, navigate to step "SolutionManager Internal Connectivity" of the Basic Configuration scenario andperform the activity “Creates RFC connectivity (WEBADMIN)”. Please referalso to the documentation available for this activity.To turn off the SAP Solution Manager maintenance mode, please starttransaction SOLMAN_SETUP, navigate to step "Configure Automatically" ofthe System Preparation scenario and perform the activity “Turn Offmaintenance mode”. Please refer also to the documentation available forthis activity.
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The Connection Test of RFC destination WEBADMIN failed in TCP/IP Connections of transaction SM59 as the following:
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Error Details    Error when opening an RFC connection (CPIC-CALL: 'ThSAPOCMINIT', communication r
Error Details    ERROR: You cannot use the gateway as a proxy for this connection
Error Details    RETURN CODE: 750
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SAP Solution Manager 7.2

gw/reg_no_conn_info, Error when opening an RFC connection, WEBADMIN, destination , KBA , SV-SMG-INS-CFG , Setup and Configuration of the Solution Manager system , SV-SMG-INS-DIA , Configuration of Root Cause Analysis related infrastructure , Problem