April, 2025 – Graham Miln

Fixing HMRC's Basic PAYE Tools for macOS

The latest version, 25.1.25092.226, of HMRC’s Basic PAYE Tools for macOS does not successfully launch. An ad-hoc code signature fixes it.

What Happens

When launched, the Basic PAYE Tools application bounces until macOS times it out. Console.app shows errors saying:

SecKeyVerifySignature failed: Error Domain=NSOSStatusErrorDomain Code=-67808 "RSA signature verification failed, no match" UserInfo={numberOfErrorsDeep=0, NSDescription=RSA signature verification failed, no match}

This is a code signing problem and needs to be dealt with by the developer.

Quick Fix

Thankfully a workaround is possible to allow the application to launch and work as usual. You can ad-hoc code sign the application to allow Basic PAYE Tools to run on your Mac.

  1. Launch Terminal.app and issue the following command:

    codesign --force -s - "/Applications/Basic PAYE Tools.app"

  2. The command will print the following line:

    /Applications/Basic PAYE Tools.app: replacing existing signature

  3. Launch the Basic PAYE Tools as usual.

Hopefully the official distribution will be fixed soon.