To digitally sign an Office document, you must have a current (not expired) digital certificate. Digital certificates are typically issued by a certificate authority (CA), which is a trusted third-party entity that issues digital certificates for use by other parties.

Microsoft first introduced the signing requirement for user mode PEs in Windows 11, version 21H2. These changes were serviced to the supported Windows client and Windows server products through Windows Update. All versions of Windows 11 natively support Trusted Signing for user mode PE files.

This article describes how you can digitally sign a macro project on Windows by using a certificate. If you don't already have a digital certificate, you'll need to get one. Tip: To use or test macro projects on your own computer, you can create your own self-signing certificate by using the Selfcert.exe tool. You'll find more details on that ...

Use this tool to find and remove specific prevalent threats and reverse the changes that they made (see Covered malware families). For comprehensive malware detection and removal, consider using Windows Defender Offline or Microsoft Safety Scanner.

Provides links to the uninstall tools and directions for many security programs.

Signing certificate To create a digital signature, you need a signing certificate, which proves identity. When you send a digitally-signed macro or document, you also send your certificate and public key. Certificates are issued by a certification authority, and like a driver’s license, can be revoked.

You can view information about a digital signature, or the certificate that is used to create the digital signature, in Word, PowerPoint, and Excel. For more information on adding or removing digital signatures, see Add or remove a digital signature.

First, you'll need to download the troubleshooter. Download troubleshooter. If you see the File Download box when you start downloading, select Run or Open. The troubleshooter provides steps for you to follow. If a program isn't listed in the uninstall options, you'll be asked for that program's product code.

At the command prompt, type MSIExec, and then press Enter. If the MSI engine is working, you should not receive any error messages, and a separate dialog box should open. This shows the MSI version. If the installer is not version 4.5, download and install Windows Installer 4.5.

Troubleshoots and fixes common issues with security and malware prevention in Windows.