Euro Customizing not confirmed, program ended

What causes this issue?

The Customizing settings which you possibly use for the euro were read
from your system. You should confirm that these settings were
determined correctly. You have denied the confirmation. The current
program, however, requires this confirmation.

System Response

The current program was ended.

How to fix this error?

Start the program again and confirm the settings found.
If you do not want to use any of the settings found for the euro, carry
out the necessary Customizing in your system and start the program
afterwards.

Error message extract from SAP system. Copyright SAP SE.