Error code 15270 appears when you are trying to download the latest tax table update in QuickBooks Desktop.

This error is caused by an incorrectly mapped shared download drive, missing payroll update files, incorrect Internet Explorer configuration, a disabled QuickBooks File Copy Service (FCS), or the system's inability to verify digital signatures.

To troubleshoot this error, try downloading the updates as an administrator, running the 'Quick Fix My Program' tool from the QuickBooks Tool Hub, and reinstalling QuickBooks Desktop if necessary.