How can I uninstall OS X Yosemite and return to OS X Mavericks?

Thank you very much!!!!

As far as I know, my mac is virtually clean. I did a completely fresh install of Yosemite, about a month ago, using a pen drive containing Yosemite, which I downloaded from the apple site. Immediatly after that install my mac has been running worse. My mouse will frequently suddenly fail to left click, keys on my keyboard will often suddenly fail to operate, browsers, especially Safari frequently crash, and my Time Machine is completely unable to recover anything prior to that instillation. My machine is a little bit slower as well. That is 'kinda' understandable, because I realize that I still have to install additional RAM to work well wt Yosemite. Still I don't see any great advancements in Yosemite, that require double the RAM. Unfortunately low RAM, isn't causing my Time Machine to not operate properly, or causing my mouse and keyboard to fail. Oh yeah, I also sporadically have WIFI issues, and device synching problems. I have an early 2009 iMac running Yosemite 10.10.1. I am not going to go back to Mavericks, because I know that Macs are frequently changing, and I'm trying to stay wt the curve. I liked Snow Leopard, but wt every new OS after that, although there are some advancements, they always seem to be chock full of problems. Does anyone have any ideas what the problems could be, or suggestions on fixing them.

The Yosemite WiFi issues are a known problem and Apple is trying to work on that (according to the response I got from my bug report). As for the RAM, ever since Lion, my personal opinion is that 8 GB is about the minimum - my MBP did not run well on 4 GB, but is doing fine with 8. My new iMac will have 16 shortly since I use that for video and graphics work. You also have to remember that you have an older machine with a less powerful processor - the new OS versions are optimized for the new hardware.

My Time Machine can not retrieve, any data that is older then the day in which I installed Yosemite. Two years of backups are now unusable, using the Time Machine interface. Increasing my RAM will not fix that issue, unless Time Machine has become more RAM hungry. I am not the only one, who has had that problem. There isn't 34 pages of posts talking about this, but there are a whole bunch of them. Unfortunately Apple isn't working on that problem. Why did Apple rush the release of Yosemite, before properly testing it. I wonder if Yosemite's problems will ever be fixed, or if users will just have to wait until the next OS. Now looking back, I would have much rather have paid for a fully tested OS (Snow Leopard wasn't free, but worked), then have been Apples test bunny. live and learn ....

Sorry to hear that; unfortunately I can't help because I've chosen not to use Time Machine as I prefer bootable clones (and I have two of each OS version I am running). I prefer those because they can be tested instantly and are the easiest way to restore if disaster strikes. Just in case there might be something here that could be of help, I'm posting the link to some TM information:

http://pondini.org/TM/FAQ.html

http://pondini.org/OSX/Home.html

greenmind wrote:

My Time Machine can not retrieve, any data that is older then the day in which I installed Yosemite. Two years of backups are now unusable, using the Time Machine interface.

Is that a universal finding that machines updated to Yosemite are unable to retrieve data from before the date of Yosemite installation or just a problem for you? I certainly wasn't aware of that limitation and was under the impression that some users in this discussion thread had used TM to return to Mavericks, but I don't recall anybody confirming that they were successful at that.

As far as having two years of backups, that would really surprise me. TM usually needs to delete the oldest files in order to make room for new ones and I'm quite sure mine never let me go back more than a year, but it would depend greatly on the amount of data backed up, the size of the TM drive and how much you update apps and data files.

Yes it does depend on the size of ones TM drive, and how often you have set the App to do backups. Time Machine not functioning after Yosemite may not a universal finding, but either is failing WiFi. Some people experience problems, while others do not. Still it is hardly a problem that only I am experiencing. Here is a full page of Apple Support Community links of people having problems using Time Machine, after the Yosemite upgrade. https://discussions.apple.com/search.jspa?facet=content&type=discussion&sort=rel evanceDesc&showAnsweredFirst=true&q=time…

I absolutely hate the new Yosemite. It always crashes and anytime I put my mac to sleep and try and start it back up the screen gets all glitchy or doesn't allow me to fill in my password. Any ideas on how to fix this? its an early 2012 macbook pro

Maybe you need to fix your Mac.

I'm not sure what prompted Allan's quick response. Probably had something to do with the unmanageable length of this discussion topic and your lack of detail on what exactly it is you want to fix.

Apple is in the best position to help you with this, either through AppleCare or at an Apple Genius bar if that's convenient. Since we can't really touch or see what you have, this forum should always be secondary to hands-on technical support.

In this forum you will always receive the fastest, most efficient help by posting a new topic and describing in great detail exactly what you are seeing, to include screen-shots where appropriate. I'm sure troubleshooters will ask you to run some diagnostics to help us see the details of what you have as far as hardware and software are concerned, but refrain from posting anything until asked since we have different ideas about what's important and interpreting the results of somebody else's work is often difficult or even wrong.

The majority of Yosemite users are not having problems with it. The problems you seem to be having are not typically seen by most users and those that do are often trying to run software from a previous OS X that needs to be updated or removed entirely.

When he started with "I absolutely hate the new Yosemite." that sort of soured me on his post.

I am following these instructions,

Partition and Format the hard drive:

1. Select Disk Utility from the main menu and click on the Continue button.
2. After DU loads select your newly installed hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed. Quit DU and return to the main menu.

I get to the 3rd part, 'click on the partition button and wait until process has completed' unfortunately i don't see a partition button, I only get apply and revert buttons and as such i am wondering which of those two it is? thank you for your help

I need help urgently here. I upgraded to Yosemite last night and realised that most of my softwares such as Photoshop and Microsoft Office don't work anymore! My Macbook Pro is a mid-2010 model. Should I reinstate back to OS Mavericks or do something else, so that all my softwares can work? My mac had a time machine backup prior to installing Yosemite, so perhaps I can reformat and restore from the backup?

Any advice here is greatly appreciated!

I don't understand why those programs are not working in Yosemite if they worked in Mavericks, but if you wish then simply erase your drive with DiskUtility (Applications > Utilities) and reinstall your backup.

Cheers

Pete

Do you have any idea if Photoshop CS and Office 2010 can work with Yosemite? They are old softwares but I'm just wondering if any upgrades or plug ins can help?