Solution : https://service.sap.com/sap/support/notes/851590 (SAP Service marketplace login required)
Key words : 
terms upgrade sp11 sp12 sdm deploy online deployment sapinst reason, /saphelp_nw70ehp1/helpdata/en/ff/c3943e9118704ba529d3266154b2cf/frameset, /saphelp_nw70ehp1/helpdata/en/43/239adcca642185e10000000a114cbd/frameset, deploy service returned error, <class_name>------------------------- loader info -------------------------classloader, error message dialog box, online deployment phase, sdm remotegui tool, symptom upgrade fails, upgrade process solution 1
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