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Compatibility issues with macOS 10.15 Catalina

On October 7, 2019, Apple released macOS 10.15 Catalina. ISC strongly recommends that Schools, Centers, and other University constituents do not upgrade, waiting until ISC has issued an update on the status of Catalina.


macOS 10.15 Catalina is the first version of macOS that does not support 32-bit applications. Since many existing applications are still 32-bit only, this lack of support may cause serious compatibility issues in Penn's computing environment. 

At this time, ISC strongly advises against upgrading until extensive testing has been completed; not only by ISC but also by local IT staff to ensure compatibility of department-specific software. For several months, ISC and others across the University have been performing vigorous testing on macOS 10.15 beta versions to identify problems and potential workarounds. However, it may take some time to determine the true scope of the issues that will arise.

Preliminary testing and analysis have shown compatibility issues with the following applications, but this list is not complete and should not be assumed to be comprehensive:


Fetch 5.7 is not 64-bit compatible. Fetch 5.8, which is currently in public beta, is 64-bit compatible but is not ready as of the macOS 10.15 release date.


DataComet-Secure is not 64-bit compatible and is unlikely to be updated for compatibility with macOS 10.15. ISC is currently investigating and has identified potential 64-bit TN3270 clients that support equivalent scripting capabilities of DataComet-Secure. Until licensing and a purchasing plan can be determined, mainframe users in particular are strongly urged not to upgrade to Catalina.

Adobe Creative Cloud 

Creative Cloud contains several 32-bit helper applications that are not macOS 10.15 compatible. Adobe plans to update all of Creative Cloud (with several notable exceptions) to 64-bit by the end of the fall. See the following link for additional information:

Symantec Endpoint Protection

SEP's current installer cannot run on macOS 10.15. Symantec reports that a macOS 10.15-native version of the installer will be available at some time post-release. A firm date is not yet available.



This page will be updated as new information becomes available.

In addition, the following article gives steps that can be used to help identify what software on your Mac is not 64-bit native.