According VPN Client GUI Error Lookup Tool
http://www.cisco.com/en/US/products/sw/secursw/ps2308/products_tech_note09186a00801f253d.shtml
Reason 413: User authentication failed.
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Description or Action:
Either the user entered wrong user authentication information, or the client was not able to launch the XAuth (user authentication) process.
M.
Hope that helps rate if it does