Mac OS: Troubleshooting Out of Memory Errors
To increase an application's memory allocation:
1. Quit the Application and return to the Finder.
2. Go to the actual application program icon (not a document created in the application or an alias to the application) and click once to select it.
3. From the File menu, select Get Info.
4. In the Get Info window, again verify that Application is listed after Kind:
5. Increase the memory in the Application Memory Size box at the bottom of the Get Info window. If you are using System 7.0, increase the Current Size. If you are using System 7.1 or greater, increase the Preferred Size. Later versions of the Mac OS have a pop up menu in the Get Info box where you select Memory. Increasing memory by 500K to 1000K should be enough in most cases.
If the program still will not open, try restarting the computer. Additional memory may be the only option of the application or file you are trying to open is fairly large. You can try using virtual memory as a temporary workaround. If you find that to solve the problem, additional memory should be installed.