Solution : https://service.sap.com/sap/support/notes/619163 (SAP Service marketplace login required)
Key words :
withholding info w4/w5, tax exempt indicator field, tax exempt indicator, tax infotypes reason, edit text field, user group basis, hr support package, change text button, irs limits infotype, relevant infotype fields
Related Notes :
| 652743 | IT0210: Erroneous Entry/Display Only Fields on Infotype |
| 638129 | IT0210: Allow screen fields to be display only |
| 411780 | Q&A: Master Note for US Tax functionality |