- AOCE The next great Macintosh Advantage ?

First, AOCE stands for Apple Open Collaboration Environment. The technology extends the operating system to provide a platform for the integration of communications, directories, and agents into the Macintosh user experience. AOCE includes a number security capabilities such as digital signatures, authentication and encryption. These technologies allow developers to create secure communications as well as the foundation for new paperless workflow applications to be built on.

- Apple Open Collaboration Environment (HTTPS)
Development of AOCE started in 1989, largely the "pet project" of Apple Fellow Gursharan Sidhu, formerly engineering lead at Apple for LaserWriter, AppleShare, and related networking products.

When the product finally shipped after years of hype, users were dismayed to find that to install it requires a machine with 2.5 MB of RAM minimum, and needed 4 MB to run well. This is the maximum available RAM in many Mac systems of the era. Removing unneeded components do little to address this, and AOCE and the other Apple technology, QuickDraw GX, typically could not be run together because of a lack of memory. While newer machines were able to run AOCE more comfortably, as an email system intended to be run on diverse networks of non-homogeneous machines the requirements greatly impaired market acceptance.

Cancellation
Adoption of AOCE among third party developers was slow due to a complicated API. The book documenting the system is larger than all of the books describing the rest of the pre-System 7 Macintosh combined. Adding a simple feature like "mail this document" to an application requires wading through hundreds of pages of documentation, and writing a core AOCE component is many times more complex.

Several parts of the AOCE engine are useful on their own, such as the Keychain. However, in order to get the keychain, the user must install all of AOCE, a cost the users were not willing to pay. Many years later the keychain was finally shipped as a stand-alone component in Mac OS 9. The encryption and signing support is arguably also useful (although not widely deployed), and it reappeared in Apple's bundled Mail application starting with Mac OS X 10.2 Jaguar in August 2002.

AOCE had one year at Apple's Worldwide Developers Conference in 1995 when it was finally selling, but by this point, the market was moving toward SMTP-based Internet mail as a universal format. By 1996 Apple had given up on AOCE, and started talking about the CyberDog project based on the OpenDoc platform. AOCE is not supported in Mac OS 7.6.

- The Roughly Drafted Review
Snowballs in Hell
Apple's ability to deliver products was increasingly being hampered by a lack of product-oriented discipline. Rather than creating insanely great products designed to sell and enrich the company in ways that would foster further great developments, Apple gravitated into the position of a research lab full of engineers working on various projects that never seemed to materialize.

The PowerTalk Disaster
PowerTalk was one of those snowballing disasters. It grew into the Apple Open Collaboration Environment, a suite of messaging technologies that picked up features as it rolled downhill: extensive foreign language support, digital signatures and encryption features, a centralized address book with a universal addressing system, and a protocol stack designed to accommodate virtually every existing messaging protocol and any others still to arrive, and an extensible information cataloging system.

The resulting suite of software was simply too much to run on existing Mac hardware, particularly when paired up with Apple's other gigantic snowball project, QuickDraw GX.
 
While software had been straining to keep up with hardware advancements in the late 80's, by the early 90's, Apple was delivering overarchitected software which was simply too much for the hardware of the time. Even for users with enough disk space and RAM to install PowerTalk, simply getting mail became a problem because individual mail items quickly ate up any remaining disk space.

Footnote - Dev Technotes for Mac OS 7.6 (WA HTTPS)

PowerTalk is neither installed nor supported. If the PowerTalk extensions are present in the System Folder at system startup, they will not be loaded. If the PowerTalk extensions are found during installation, they are removed.

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it requires a machine with 2.5 MB of RAM minimum, and needed 4 MB to run well. This is the maximum available RAM in many Mac systems of the era.