Solution : https://service.sap.com/sap/support/notes/402180 (SAP Service marketplace login required)
Key words : 
account assignment object pm / cs order, system displays error message m2802, display pm/cs orders, actual costs reason, program error, planned costs, exchange rate, euro currency, pmis customizing, statistics currency
Related Notes : 
       
| 449787 | |
| 120713 | Euro exchange rates in TCURR fr. 1/1/1800 or earlier |