SYNOPSIS

Generates an HTML email signature for Microsoft Outlook using Base64 encoded images.

DESCRIPTION
This script creates Outlook signatures using Base64 encoded images instead of downloading external files. All logos are embedded directly in the HTML, making the signatures more portable and reliable. Includes support for multiple templates, backup functionality, and Microsoft Graph API integration.

REQUIREMENTS

• PowerShell 5.1 or later
• Microsoft Graph API access
• Outlook 2016 or later
• Windows 10/11

PARAMETER -Logo
Specifies which logo to use in the signature. Available options:

• Logo-Default (default)
• Logo-Default2
• Logo-Default3
• Logo-SecondaryDomain
• Logo-Alternative

EXAMPLE
-Logo Logo-Default2

PARAMETER -User
Specify a User. Files will be saved to C:\Temp\Signatures

EXAMPLE
-User JDoe

PARAMETER -Cleanup
Cleans Outlook Registry keys and backs up existing signatures to C:\Users\USERNAME\Documents\Outlook Signatures Backup Deletes content from %APPDATA%\Microsoft\Signatures Use this when troubleshooting signature issues.

EXAMPLE
-Cleanup

CHANGELOG

To Do

• Convert Address information to new formatting with UTC Time-Zone
• Troubleshoot Environet default settings via Registry (currently works if capitalize the E in file name)
• Research/Test further Registry settings
• Test on fresh machine, review virgin registry keys and settings

Version 1.0.0

• Complete rebuild of syntax for PowerShell Core (v5.1) compatibility
• Now works in TRMM
• Redesign default logo
• Redesign GSIVET logo
• Removed -Template parameter, Logo auto-assigns appropriate template
• Added registry cleaning to -Cleanup
• Added multiple registry settings
  • Disabled Outlook New
  • Disabled Outlook New Nag notifications
  • Delete hardcoded Outlook New switchover date
  • Enabled Signature Cloud upload and sync
• Improve terminal output messaging
• Verbose logfile for troubleshooting

Version 0.3.0

• Complete rebuild with embedded HTML templates
• Removed template file dependencies
• Automatic template selection based on logo
• Enhanced Environet account detection and handling
• Dual mailbox signature configuration
• Registry settings for both primary and secondary mailboxes
• Detailed execution logging system
• Base64 encoded logos
• Improved resource management and cleanup
• Simplified logo selection process
• Enhanced error handling and logging

Version 0.2.0

• Removed dependency on external image files
• Added Base64 encoded images
• Rewrote HTML code to support New Outlook and OWA
• Added automatic signature backup
• Added -Cleanup parameter for signature management
• Added registry settings for New Outlook and OWA
• Added phone number formatting
• Added Outlook version detection
• Improved parameter validation
• Improved formatting and efficiency of code
• Added ability to easily add alternative templates with switch -Template

Version 0.1.5

• Fixed -Logo parameter to work correctly in Tactical RMM
• All non SecondaryDomain email accounts have logoName added to the filenames to allow for multiple signatures
• Cleaned up Output to be more readable

Version 0.1.4

• You can now define a specific user with .\Set-OutlookSignatures.ps1 -User JDoe or -User JDoe in TRMM field
  • Run the script on your computer with -User JDoe and it will save to your C:\Temp\Signatures
• Finished all templates
• Fixed Registry settings, no longer greys options out and recursively scans for existing Profiles
• Further optimized logic flow and Functions
• Added more helpers for converting variables to convert phone number formatting
• Greatly improved logging and debug details saved in LogFile
• Added token caching to reduce API calls and improve performance
• Implemented retry logic for logo downloads with proper resource cleanup
• Added automatic cleanup of signatures
• Enhanced error handling with detailed JSON logging
• Fixed line spacing issues in log output
• Improved registry handling to properly clear existing signatures before setting new ones
• Added WebClient implementation for better download performance
• Added proper resource disposal for web requests

Version 0.1.3

• Added support for testing against a specific user.
• Finished Environet New Email template.
• Optimized logic flow and Functions.
• Added new helpers for converting variables to all Uppercase or Lowercase.
• Added more logging information for SecondaryDomain.
• Enhanced script output with more information and better readibility.

Version 0.1.2

• Set Microsoft Graph with registered Entra App as default method for pulling user information.
• Checks if user has an SecondaryDomain account
• Began HTML template to generate SecondaryDomain "New Email" signatures

Version 0.1.1

• Enhanced registry settings to manage Outlook's default signature configuration.
• Added checks to remove "First Run" registry entry to ensure users can modify the default signatures.
• Ensured DisableRoamingSignatures and DisableRoamingSignaturesTemporaryToggle are set to allow for roaming signatures.

Version 0.1.0

• Initial script to generate signatures dynamically