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All of this was mitigated by the ease with which extensions and the operating system itself could be swapped in and out: Instead of modifying configuration files as on other operating systems, extensions and other automatically run software simply had to reside in a particular subfolder of the System
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were third party utilities that automatically detected conflicts and problematic extensions and other software executing at boot, otherwise a time-consuming task that required users to turn off extensions in sets until they found the conflict, as well as allowing load order to be altered without
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for each System subfolder. In addition, the Mac was perfectly happy to have two (or more) System
Folders present on a hard drive. Only the "blessed" System Folder would be loaded at startup. So, when a new version of the operating system was to be installed, or a new application, the user could
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The most common time for extension conflicts to start was the release of a new version of the operating system, followed closely by the installation of a complex new application that either conflicted with existing extensions, or installed extensions that conflicted with the existing set.
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and general instability. Some users happily loaded every extension they could find on their computer, with little or no impact. Others fastidiously avoided any non-essential extensions as a way of avoiding the problem. Many were judicious in the addition of extensions.
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renaming items. Extensions were only loaded at startup time, meaning that any attempted change required a reboot.
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easily duplicate the system folder, perform the install, and then fall back if a problem resulted.
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were installed as extensions. In addition, a number of applications, especially
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In addition, extensions sometimes competed for system resources with
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This problem increased during the mid-1990s as resource-hungry
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328:. Sebastopol, CA: O'Reilly & Associates, Inc. pp.
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Extension conflicts came to an end with the release of
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353:Now Startup Manager 7.0 Versus Conflict Catcher 3
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106:Learn how and when to remove this message
291:Stauffer, Todd; McElhearn, Kirk (2004).
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38:Please help
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278:References
230:user space
193:Apple menu
166:multimedia
135:Extensions
66:newspapers
170:QuickTime
398:Category
368:Mac OS X
262:JAR hell
257:DLL hell
236:See also
222:Mac OS X
143:OS calls
131:System 7
158:crashes
80:scholar
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147:Finder
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