Run a Unibin in Rosetta!

by coelomic

How do you reset an application to run under Rosetta instead of natively? Why would you want to do that? Wouldn’t it be slower?

Forcing a Universal Application to Run with Rosetta” on Apple’s Support Site.

In basic terms, this document provides instructions on how to use a new application written for either an Intel-based or PowerPC-based Mac as if it was an older application written for a PowerPC-based model using an Intel-based system. It sounds convoluted, but it’s actually quite easy.

Apple explains how to force a Universal application to open using Rosetta:

1. Click the application’s icon in the Finder.
2. From the Finder File menu, choose Get Info (Command-I).
3. Select the checkbox named “Open using Rosetta.”
4. Close the Get Info window.

Apple mentions that you might want to do this in order to use a new Universal Internet or graphics application with an older plug-in that was written for PowerPC-based Macs. Although the application runs natively, since the plug-in does not, the application cannot natively take advantage of the capabilities provided by the plug-in.

Real world examples of the reasons to do this include, running the Universal version of the Safari web browser within Rosetta in order to run the older Shockwave plug-in, and running future Universal versions of Photoshop, which is not yet native for Intel-based systems, with older plug-ins.

Running the Universal application within Rosetta will make the application run more slowly than it would if it was running as a native application. What is lost in terms of speed is a tradeoff for the ability to run non-unibin plugins and the like.

Examples courtesy of