Group liabilities incomplete - the rate for & & is missing in TCURR

What causes this issue?

The exchange rate of company code currency &V1& is not maintained in
local currency &V2& of the company code displayed; the group liabilities
only contain the amounts in the currencies here for which exchange rates
could be found.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Define the missing exchange rate.

Error message extract from SAP system. Copyright SAP SE.