ERROR-Agent is blocked. Blocked reason is: Agent is out-of-sync with repository

Yesterday I faced Below error when I was trying to upload agent :-

hostname:agent:AGENT_HOME/bin> ./emctl upload

Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0

Copyright (c) 1996, 2010 Oracle Corporation.  All rights reserved.

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EMD upload error: uploadXMLFiles skipped :: OMS version not checked yet. If this issue persists check trace files for ping to OMS

hostname:agent:AGENT_HOME/bin> ./emctl pingOMS
Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0
Copyright (c) 1996, 2010 Oracle Corporation.  All rights reserved.
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EMD pingOMS error: Invalid ping response "ERROR-Agent is blocked. Blocked reason is: Agent is out-of-sync with repository. This mos reinstalled or recovered. Please contact an EM administrator to unblock the agent by performing an agent resync from the console. P nblock the agent"

Solution :-

Login to Problamatic agent :-

1. Stop the agent :-

AGENT_HOME/BIN> ./emctl stop agent 

2. Secure the agent which will generate a new key :-

AGENT_HOME/BIN> ./emctl secure agent 

3. Start the agent: 

AGENT_HOME/BIN> ./emctl start agent 

4. Login to the OEM Grid Console :-

Navigate to Setup >> Agents >> problematic agent home page >> Click on Agent resynchronization

Once synchronization completed.

5. Try to ping OMS

AGENT_HOME/BIN> ./emctl pingOMS

6. Once Ping Successful . Try to upload the agent

AGENT_HOME/BIN> ./emctl upload 

Agent is now sync with repository

I hope this article helped you.

Thanks
Amit Rath