2101312 - Error occurred while trying to evaluate condition of a process step

In Purchase Order upon clicking on Order button or whiel approving Purchase order or when trying to post a supplier invoice you receive the following error messages:

• Document not submitted for approval; inconsistencies exist;
• Exchange Rate for and for Rate Type does not exist for;
• Error occurred while trying to evaluate condition of a process step.

 or

 You may see below error

Exchange rate A/B on XX.XX.XXX missing for currency conversion*

SAP Business ByDesign

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