If you are unable to use Payroll, Tools, Download Taxes to install the payroll tax update, this article outlines the process to download and install the tax update manually from the Knowledgebase.
See the Payroll tax release notes for changes included in the tax update:
Warning: Download and update taxes in each company data folder that does not share a tax file. After you complete this update and have run Update Taxes in Payroll, tax changes are effective the next time you process payroll, regardless of the effective date on the tax table or the dates on the check. Tax updates do not affect previously issued checks.