You created a Supplier Invoice without Purchase Order and entered all the details but Total Gross Amount and Total Tax Amount not be calculated automatically. Always you need to press Calculate Total Amount button to get the correct values.
Total Gross Amount and Total Tax Amount not calculated automatically to avoid inconsistent data between system data (automatically calculated) and data on Paper Invoice.
Please consider following Use Case:
A user has entered everything correct but wrong invoice value at certain invoice item and the system calculated the total tax amount and total gross amount automatically.
And the user didn't check these two values carefully or just oversees them, then the invoice will be posted with error!
To avoid such kind of problem, user has to click the button by himself because this is manual invoice because we want ensure that the user will compare the calculated value with the value on paper invoice.
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