Multi-User iMessage Setup on a Single Mac with myCRMSIM

You can enable multiple iMessage accounts to operate simultaneously on a single Mac machine using multiple macOS user profiles.

🧰 Prerequisites 

• A Mac machine with sufficient RAM (more memory allows for more active iMessage connections).

• A myCRMSIM iMessage account with multiple numbers.

• Multiple iMessage accounts (Apple IDs).

• Associated iPhones for each iMessage account.

• Admin access to the Mac for creating multiple user profiles

🛠️ Step-by-Step Setup and associated links 

1. Create Separate macOS User Profiles

• On your Mac, go to System Settings > Users & Groups.

• Create a new user account for each iMessage account you want to run.

• Ensure these are standard user accounts, not guest accounts.

2. Follow our install and setup procedure in each User account

• Within each user profile, sign in to Messages (iMessage) using the relevant Apple ID.

• Pair the iMessage account with the associated iPhone

3. Install the myCRMSIM SMS Gateway App

• Download and install the mySMS Gateway App into the new user account

• Complete the installation within the new profile and allow necessary permissions as per our install setup guide

4. Enable Background Operation via Smart Switching

• Use fast user switching to change between profiles (not full logout/login). This allows iMessage to continue running in the background.

• Enable this in System Settings > Control Center > Fast User Switching.

5. Prevent Sleep & Enable Auto-Start

• The mySMS Gateway App prevents your Mac from going to sleep to maintain iMessage uptime.

• In System Preferences > Energy Saver, enable:

  • ✅ Prevent computer from sleeping automatically when the display is off

  • ✅ Wake for network access

• Also, enable:

  • ✅ “Automatically turn back on after a power failure” under System Preferences > Energy Saver.

• In the mySMS Gateway App Settings, enable:

• ✅ “Startup with macOS” to ensure the app auto-starts on login.

⚠️ Important Considerations

 

• 💻 Performance Tip: System performance and stability depend on the Mac’s memory and CPU:

• Recommended Maximum: To reduce the risk of getting flagged we recommend to keep it to maximum 4 iPhones and associated iMessage accounts running on any one single machine.

• 🚫 Anti-Flagging Warning: Running more than 4 iMessage instances on one Mac may risk detection or account flagging by Apple.