10000001 
Message
This invoice cannot contain both liable and exempt rows
Diagnosis
You have tried to create an A/P Invoice of Service type that contains at least one row that is tax liable and at least one row that is tax exempt, for a vendor that is specified as Self-Employed (in 
Business Partners 
Business Partner
Master Data Accounting Tab Tax 
subtab) .
Procedure
Create one A/P Invoice of Service type for the rows that are tax liable and one A/P Invoice for the tax-exempt rows.