Look what I found:
OS X v10.10 Developer Preview 1 is pre-release software. Do not use this pre-release software in a commercial operating environment or with important data. You should back up all of your data before installing this software and regularly back up data while using the software.
If an installation of OS X v10.10 Developer Preview 1 fails, try using Disk Utility from a Recovery HD to repair the disk.
This build is being provided to you for testing and development purposes. Should you encounter any problems, submit a bug report using the online Bug Reporter at http://bugreporter.apple.com/. Please make sure to include “10.10 (14A238x)” in the bug title and description. This information will ensure that your bug is processed quickly.
When submitting a bug report, make sure to include a Summary, Steps to Reproduce, Expected Results, Actual Results, and the diagnostic output generated by running sudo sysdiagnose in Terminal, or use the special key chord Control-Option-Command-Shift-Period.
For complete instructions on submitting bug reports, visit the Bug Reporting page at http://developer.apple.com/bugreporter/.
Developer Preview System Requirements
The OS X v10.10 Developer Preview supports the following Macs:
iMac (Mid 2007 or newer)
MacBook Air (Late 2008 or newer)
MacBook (Late 2008 Aluminum, or Early 2009 or newer)
Mac mini (Early 2009 or newer)
MacBook Pro (Mid/Late 2007 or newer)
Mac Pro (Early 2008 or newer)
Xserve (Early 2009)
Notes and Known Issues
Migration Assistant may hang while transferring your information from a Time Machine backup. To proceed with the login, quit the Installer.
Developer Preview 1 may be unable to install over an encrypted volume.
Choosing a later installation from the Software Update notification may fail to install selected updates.
The system may appear to hang if the Login password does not match the OpenDirectory or keychain password. Pressing the Esc key will allow the login to proceed.
Some all day events may not be displayed. Navigating to a different day, and back will display the missing events.
Some apps that use Handoff will mistakenly show as Safari in the iOS lock screen and OS X Dock.
In some cases, not all devices associated with an Apple ID will pair successfully. These devices will be unable to use Handoff, Phone calls, or Instant HotSpot.
When using a Mac, Handoff may sometimes stop showing icons on other iOS and OS X devices.
Handoff-based Bluetooth connections between devices may stop working after trying to use Handoff.
In some cases, using Handoff with Safari will result in an old URL being resumed instead of the current URL.
Directions and Navigation in Maps does not work with Handoff in Developer Preview 1.
Phone calls to and from the Mac may sometimes not complete or send and receive audio.
Dictation shortcut text field is missing from Dictation preferences.
Opening the Customize Commands of the Dictation preference panel may cause System Preferences to hang.
ShareKit extensions may crash when the Share sheet is closed.
Finder Sync extensions may not function correctly.
Shared purchase history page on Mac App Store and iOS App Store are disabled.
Viewing of Family purchases is not available in Developer Preview 1.
Items already owned by family members must be re-downloaded from the Purchased page (not Store pages) to get them free of additional charge. .
Under 13 account creation is disabled in Developer Preview 1.
While using the iTunes Store you may experience a spinner that never completes. Log out and back in to iTunes to correct the issue.
Email invitations are not enabled; members can join using push notifications or via inline password entry flow.
Notifications for “Ask to Buy” are not available on older clients. After parental approval, kids will have to reinitiate the purchase.
You can’t approve an “Ask to Buy” request from the requestor’s iOS device.
Streaming video from iCloud may present a black screen. Downloading the video will allow playback.
Some graphical corruption may be visible when using Icon View in Finder.
iCloud Documents & Data created with Developer Preview 1 will be deleted from the servers at some point during the beta period. Your devices using Developer Preview 1 will maintain copies of those deleted iCloud Documents & Data. After the server deletes that data, all iCloud Documents & Data you previously used on OS X v10.9 and earlier or iOS 7 and earlier will be copied on the server over to the OS X v10.10/iOS 8 version of iCloud Documents & Data. Your devices using Developer Preview 1 will then re-upload their copies to the servers. If you delete those copies on your Mac before they are uploaded to the servers, and if you don’t have a backup of them, those documents will be lost. Documents and data managed on earlier releases of OS X and iOS will not be affected by any of this.
The Web UI for managing iCloud Documents & Data does not show the documents and data managed by systems running Developer Preview 1. Documents and data synced with previous operating systems will be displayed.
Changes to iCloud Documents & Data in Pages, Numbers, and Keynote on Macs using OS X v10.10 Developer Preview are only available on other devices using OS X v10.10 Developer Preview or iOS 8.0 beta. Any changes from devices using earlier versions of OS X or iOS will not be available. Changes will also not be visible in Pages, Numbers, and Keynote on iCloud.com.
Some account password prompts may request the same login information several times before dismissing.
Finder may spin after adding a large number of items to iCloud Drive.
iCloud settings for My Photo Stream and Shared Streams will be preserved from earlier versions of OS X on upgrade to Developer Preview 1. However, turning off Shared Streams will turn off My Photo Stream, and visa versa.
Turning off My Photo Stream or Shared Streams may not be available in System or Application preferences after upgrading to Developer Preview 1.
Mail may not be able to set up new Mail accounts within the Mail application.
The Markup Signature panel may not detect touchpad events.
Markup Annotations cannot be modified after clicking Done.
Markup panel may not display toolbar when invoked.
Old iMessages stored on your computer are incorrectly deleted when upgrading to OS X v10.10 Developer Preview. Backup your Messages in ~/Library/Messages before upgrading.
Video Recordings of attached iOS devices running iOS 8.0 beta 1 may flicker and have audio/video timing issues.
The Remote Desktop Admin Application may be unable to download client installers.
Apple Remote Desktop feature Changing Client Settings is not supported for Developer Preview 1.
Some panels and buttons may not be accessible or operate as expected.
Subpixel rendering is now on by default for all web content. Web sites or in-app web views with extremely tight design constraints may render differently.
Typing a partial site name and pressing Return can cause navigation to a search engine result page instead of the expected navigation to a commonly visited website identified as a Top Hit.
Typing a multi-word search term and pressing Return can cause inadvertent site-specific searches instead of the expected web search engine search result page.
The selected tab when searching for an iCloud tab from another device may not be the tab opened.
Smart Search Field stop/reload button, one step button, and other smart search field controls are not accessible.
Using Safari Test Drive on multiple systems which are configured to sync Chrome or Firefox bookmarks to Chrome/Firefox cloud-based sync services may cause duplication of bookmarks.
Date & Size limits set in Safari are not enforced in Developer Preview 1.
Safari may stop responding while loading video when playing Netflix content.
When changing languages while playing Netflix content, it may take several seconds for the audio to switch to the new language.
Keystrokes may trigger alert sound when in Netflix full-screen playback mode.
Systems running Developer Preview 1 may be unable to connect to share points over SMB.
Systems with earlier versions of OS X may not be able to connect to a server running Developer Preview 1 over SSL.
In Developer Preview 1 unsigned or improperly signed kexts will not be loaded. To use unsigned kexts during development, this strict check can be disabled by adding a “kext-dev-mode=1” boot arg.
AVFoundation changes the way some ID3 metadata values are represented as AVMetadataItems for binaries that are linked with the Developer Preview 1 SDK.
Installing kernel extensions on systems running Developer Preview 1 may make your system un-bootable. To fix the issue, boot into the Recovery Partition and run the following:
kextcache -u /Volumes/
Some Apple Script Editor toolbar buttons may not enable/disable properly. The menu items can be used instead.
Some text may not be localized to the selected system language.
Some languages may have clipped or misaligned layout.
Some Accessibility features may not function correctly in Developer Preview 1.
Some panels may appear transparent.
The Print panel may not appear in some applications.
Applications that are not compatible with Developer Preview 1 may hang before presenting an incorrect error.
Some 64-bit preference panels may fail to load after restarting System Preferences in 64-bit mode. Relaunching System Preferences resolves the issue.
Netboot may fail to find local drives and shutdown.
Systems without a display attached may experience decreased performance.
PhotoBooth is not included in this developer preview.
Auto-Submission of Diagnostic and Usage Data
By default, OS X v10.10 Developer Preview builds automatically send anonymous diagnostic and usage data back to Apple. This includes information about crashes, freezes, kernel panics, and information about how you use Apple and third-party software, hardware, and services. This information is used to help Apple improve the quality and performance of its products and services. The preference is cleared in this seed. This will allow the collection of anonymous diagnostic and usage data to help deliver a high quality release for our customers. If necessary, this setting can be disabled in the Privacy tab in the Security & Privacy preferences pane.
The pre-release software identified above is Apple Confidential Information and your use of such software is subject to your Registered Apple Developer Agreement and Mac Developer Program License Agreement. Distributing such pre-release software to anyone other than another Registered Apple Developer who is working for the same entity as you is considered a violation of your agreement with Apple and is damaging to both Apple and those who develop for the Apple platform. We sincerely appreciate your efforts to keep this pre-release software Confidential. You agree that you will not export or reexport any of the software or Confidential Information received from Apple (a) into (or to a national or resident of) any U.S. embargoed countries (currently, Cuba, Iran, North Korea, Sudan, or Syria) without first obtaining proper authorization from the U.S. Government; or (b) to anyone on the U.S. Treasury Department’s list of Specially Designated Nationals or the U.S. Department of Commerce Denied Person’s List or Entity List. You also agree that you will not use said software for any purposes where prohibited by United States law, including, without limitation, the development, design, manufacture, or production of nuclear, missile, chemical, or biological weapons.
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