You try to enter a Service (which you marked as expense in service master data) in the project in the work tab or expense tab you will get this error.
Where ABC is the service ID
SAP Business ByDesign
Currently in projects we do not support Service expense products, neither under work tab nor under expense tab.
Not as a work, because time confirmations are not allowed for expense products and not as an expense, because only expense accounts can be entered on tab “Expenses”currently.
This was never developed in standard ByDesign system so we considered it as new requirement so submit all new requirements on Customer Influence Forum at https://influence.sap.com/sap/ino/#/campaign/886
To know if there is other way to achieve your requirement which may be other customers or partners or our developers can sujjest ,kindly submit all such consulting questions in SAP community at https://www.sap.com/community/tag.html?id=01200615320800000691
expense service, service expense , KBA , SRD-PRO-PMN , Project Management , Problem