Hi Satish
No problem at all kindly take a look at the following documentation help guides for task assignment and registration:
http://help.sap.com/saphelp_nw73ehp1/helpdata/EN/0e/57827af0e34edfacd4c82edeb6acca/content.htm
http://help.sap.com/saphelp_nw73/helpdata/en/8b/4c9559d03640b1b798f25895936f22/frameset.htm
Kindly update me as per your findings.
Kind Regards & All The Best
Troy Cronin - Enterprise Portal Support Engineer
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