macOS Catalina Not Running Your Apps? Here’s How to Fix the 32-bit App Problem

With macOS Catalina, Apple made a big leap: it completely dropped support for 32-bit apps. That means if you’re trying to launch an older app and you see the message:

“App needs to be updated. The developer of this app needs to update it to work with this version of macOS”

— you’re dealing with an app that’s no longer supported. Here’s how to check which of your apps are affected and what you can do to fix it.

Why It Happens

Catalina only runs 64-bit apps. Older 32-bit apps won’t work — they’ll crash or won’t open at all. This includes older versions of popular software, older games, utilities, or drivers that haven’t been updated in years.

How to Check if an App Is 32-bit or 64-bit

Click the Apple logo  at the top-left of your screen
Choose About This Mac
Click System Report
Under the sidebar, go to Software > Applications
In the list of installed apps, look for the 64-Bit (Intel) column
- If it says No, the app is 32-bit and won’t work in Catalina
- If it says Yes, it’s 64-bit and should be fine

💡 You can also sort by the “64-Bit (Intel)” column to group incompatible apps together.

What to Do If an App Won’t Open in Catalina

✅ Check for an Update

Open the app and check for a “Check for Updates” option
Visit the app developer’s website and look for a Catalina-compatible version

💸 Be Prepared to Pay

Some developers require you to buy a newer version of the app to get 64-bit support

🔄 Look for Alternatives

Many free or open-source alternatives exist for older apps:

Use App Store search or sites like AlternativeTo.net to find Catalina-compatible tools

Bonus Tip: Check Before Upgrading

If you’re reading this before installing Catalina:

Run Go64 (a free app by St. Clair Software) to scan your Mac for 32-bit apps before you upgrade.