Item &: maximum warehouse stock level exceeded

What causes this issue?

The warehouse stock on hand of item &V1& would increase by more than
9.999.999.999,999 SKUs as a result of this inward posting. This is not
allowed for technical reasons.

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?

Check the quantity entered in the <GL:unit_of_entry>unit of entry</>.
Should the stock level really be as high as this, this would mean that
the <GL:stockkeeping_unit>stockkeeping unit</> is unsuitable for the
inventory management system. Contact your systems administrator.

Error message extract from SAP system. Copyright SAP SE.