Apple Seeds New Beta of OS X Mountain Lion 10.8.1 to Developers - MacRumors
Skip to Content

Apple Seeds New Beta of OS X Mountain Lion 10.8.1 to Developers

by

Apple has seeded a new beta of OS X 10.8.1 to developers, exactly a week after the first build came out, according to 9to5Mac.

The release has a build number of 12B17 and Apple reports no known issues, but asks developers to focus on a wide variety of areas for their testing. The delta update -- where only items that have changed are downloaded -- weighs in at 43.27MB.

Mountainlionbeta
According to 9to5Mac, developers have been asked to test Active Directory, Microsoft Exchange in Mail, PAC proxies in Safari, SMB, USB, and Wi-Fi and audio when connected to the Apple Thunderbolt display -- the same list of items as the prior release.

The OS X 10.8.1 seed is available for download via the OS X Developer portal at developer.apple.com.

Top Rated Comments

186 months ago
No, I haven't installed it - but I have been following the various reports of hard crashes, absurdly short battery life and iOS-like oddities. And it doesn't seem that great to me.

So whining about something you've never even tried. Thanks, that's useful.

There are always problems with any release of any software, OS or otherwise, so anyone could declare any release a "train wreck" if the only basis for that is some people reporting problems online.

What really matters is how widespread problems are and how severe they are. Problems are to be expected for any .0 release, and for a .0 release it's surprisingly solid (heck of a lot better than 10.7.0, and I suspect better than 10.7.4 for most people).

It's just common knowledge, anyone doing mission critical work or otherwise sensitive to issues should skip all .0 releases (and often one or two after that). And those that do need not regale us with whining about problems they've just heard about, that adds nothing to the discussion.
Score: 9 Votes (Like | Disagree)
186 months ago
Possible release next week since there are no known issues.

All things considered Mountain Lion has been pretty much problem free for a 10.x.0 release.

Then please, read every post in this thread:

https://discussions.apple.com/thread/4135250?start=0&tstart=0

and then report back :P
Score: 8 Votes (Like | Disagree)
Cynicalone Avatar
186 months ago
Possible release next week since there are no known issues.

All things considered Mountain Lion has been pretty much problem free for a 10.x.0 release.
Score: 7 Votes (Like | Disagree)
mw360 Avatar
186 months ago
So, still no fix for the "weighs in at" issue. :rolleyes:
Score: 6 Votes (Like | Disagree)
Kariya Avatar
186 months ago
Install the OS and see for yourself if it really is that terrible instead of complaining for the sake of complaining.

As it stands you're just whining and whining...and its quite annoying to read in every other thread one comes across.
Score: 4 Votes (Like | Disagree)
186 months ago
And people CONTINUE to spout the same nonsense about the purported advantages of a "clean install" - for every five positive reports, I can show you five OTHER reports in these forums from users who have the same if not worse problems AFTER a clean install.

So let's stop with this placebo recipe, shall we?[COLOR="#808080"]

I did a clean install. It worked for ME, perhaps it will not work for YOU or OTHER people but it worked for ME. A clean install of a new OS is never a bad thing to get rid of left over files here and there.

It's not the end all be all solution to anything, but it can be beneficial. I know you do not think so but so far as I can tell you don't like much of anything.
Score: 4 Votes (Like | Disagree)

Popular Stories

apple pro tell logo

Apple Launching Five New Products Today

Thursday November 5, 2026 12:59 am PST by
Apple is launching five new products on Friday, November 6, following pre-orders that opened last week, including its first touchscreen MacBook Pro models. The following new products will be available from today: iPad mini with OLED display and A20 Pro chip iMac with M6 chip 14-inch MacBook Pro with M6 chip 14-inch MacBook Pro with OLED touchscreen 16-inch MacBook Pro with OLED...
duo aquarium

More Fun iPhone Duo Apps: 30 New Picks to Try

Friday November 6, 2026 3:27 pm PST by
When the iPhone Duo launched, we shared a list of some of the fun apps developers created for the new form factor. Two weeks out, developers are continuing to come up with fresh ideas, so we thought we'd share some of our favorites. Games Marbles Unhinged ($2.99) - Marbles Unhinged is a marble maze designed for the Duo. When you fold it, the floor turns into a ramp. If you stand the top...
silver iphone 18 pro

Apple Rumored to Drop the iPhone's Action Button Next Year

Friday November 6, 2026 6:07 am PST by
Apple plans to merge the iPhone's Action button with the Camera Control starting next year, according to the leaker known as "Instant Digital." In a new post on Weibo, the leaker claimed that a single press of the combined button would open the camera, while a long press would trigger the function assigned to the Action button. They explicitly clarified that the dedicated Action button would ...
Latest Stories
Early Apple Black Friday Deals on Apple Watch, MacBook Air, and More
Early Apple Black Friday Deals on Apple Watch, MacBook Air, and More
15 hours ago
'Backglow' Lets You Customize New MacBook Pro's Glowing Apple Logo
'Backglow' Lets You Customize New MacBook Pro's Glowing Apple Logo
15 hours ago
Top Stories: Apple Product Launches, iOS 27.3 Beta, and More
Top Stories: Apple Product Launches, iOS 27.3 Beta, and More
22 hours ago
More Fun iPhone Duo Apps: 30 New Picks to Try
More Fun iPhone Duo Apps: 30 New Picks to Try
2 days ago
Hands-On With Apple's New OLED Touchscreen MacBook Pro
Hands-On With Apple's New OLED Touchscreen MacBook Pro
2 days ago
Apple Store With All-New Design Opening Soon in Southern California
Apple Store With All-New Design Opening Soon in Southern California
2 days ago
Control the Glowing Apple Logo on Your New MacBook Pro
Control the Glowing Apple Logo on Your New MacBook Pro
2 days ago
Apple Shares New 'Apple Card: Apply and Use in Minutes' Ad
Apple Shares New 'Apple Card: Apply and Use in Minutes' Ad
2 days ago
Apple Says More Than 100,000 Apps Optimized for iPhone Duo, Here's What's Still Missing
Apple Says More Than 100,000 Apps Optimized for iPhone Duo, Here's What's Still Missing
2 days ago
Early Black Friday Deals Kickoff With Steep Discounts on Apple Watch Ultras and More
Early Black Friday Deals Kickoff With Steep Discounts on Apple Watch Ultras and More
2 days ago
The MacRumors Show: iOS 27.3 Looks Like a Huge Update
The MacRumors Show: iOS 27.3 Looks Like a Huge Update
2 days ago
Best Buy's Black Friday Event Begins With Sitewide Savings on Apple, TVs, More
Best Buy's Black Friday Event Begins With Sitewide Savings on Apple, TVs, More
2 days ago
Apple Releasing Yet Another Two New Products Next Week
Apple Releasing Yet Another Two New Products Next Week
2 days ago
MacBook Air Drops to Lowest Price in Months With Amazon's $250 Discount
MacBook Air Drops to Lowest Price in Months With Amazon's $250 Discount
2 days ago
Apple Rumored to Drop the iPhone's Action Button Next Year
Apple Rumored to Drop the iPhone's Action Button Next Year
2 days ago
Apple's Extended Return Policy Now in Effect for 2026 Holiday Season
Apple's Extended Return Policy Now in Effect for 2026 Holiday Season
2 days ago
Apple Music Classical Updated With New Icon and Refreshed Design
Apple Music Classical Updated With New Icon and Refreshed Design
2 days ago
OLED iPad Mini, M6 iMac, and New MacBook Pros Available From Today
OLED iPad Mini, M6 iMac, and New MacBook Pros Available From Today
2 days ago
Apple Surveys iPhone Duo Buyers About Crease and Camera
Apple Surveys iPhone Duo Buyers About Crease and Camera
3 days ago
Apple's First Touchscreen Mac is Now Arriving to Customers
Apple's First Touchscreen Mac is Now Arriving to Customers
3 days ago
Claude Gets Personal Finance Feature With Bank Account Linking
Claude Gets Personal Finance Feature With Bank Account Linking
3 days ago
Apple Arcade Adds Crossy Road Rush and NBA 2K27
Apple Arcade Adds Crossy Road Rush and NBA 2K27
3 days ago
Apple's New HomeView Smart Home Hub: Here's How Much RAM It Has
Apple's New HomeView Smart Home Hub: Here's How Much RAM It Has
3 days ago
iPad Mini vs. iPad Air Buyer's Guide: Now Just $50 Apart
iPad Mini vs. iPad Air Buyer's Guide: Now Just $50 Apart
3 days ago
First iOS 27.3 and macOS Golden Gate 27.3 Public Betas Now Available
First iOS 27.3 and macOS Golden Gate 27.3 Public Betas Now Available
3 days ago
Apple Announces a New Mac Sales Record
Apple Announces a New Mac Sales Record
3 days ago
Paid $200 for Logic Pro? Apple Says You Won't Get This New Feature
Paid $200 for Logic Pro? Apple Says You Won't Get This New Feature
3 days ago
Instagram's Edits Video Editor is Now Available on Mac
Instagram's Edits Video Editor is Now Available on Mac
3 days ago
Prevent Siri and Search From Accessing Specific iPhone Apps
Prevent Siri and Search From Accessing Specific iPhone Apps
3 days ago
Best Early Black Friday Deals on iPhone 18 Pro and iPhone Duo
Best Early Black Friday Deals on iPhone 18 Pro and iPhone Duo
3 days ago