Upgraded to 11.04 and want to downgrade to 10.10 or 10.04

You will have to reinstall... The package managers don't support a "backdown" mode, AFAIK.

If you have separated / and /home, then you can do this without affecting your home folder..

Actually, I tell a lie; but not too much of a lie. Downgrading is not "supported", per se, but it is possible to pin, or specify a version. This may break dependency resolution however.

https://help.ubuntu.com/community/DowngradeHowto

@mycae
That document is a couple of years old, only suggests that it be used for Ubuntu 8.10 and lower, and itself warns that it is likely not to work. Has anybody successfully used those instructions lately?

@Calgar Dursun
When you post in a question thread started by someone else, please do not use the "Add Answer" button unless you are proposing a solution for use by the person who created the question. (Similarly, you should only click "Add Information Request" if you are asking that person for information for the purpose of pursuing a solution to their problem.) In other cases, please use the "Just Add a Comment" button, which never changes the status of a question.

"This is the worst version The canonical ever done."
It may be the worst version for your needs; in that case, you should not use it. Ubuntu 11.04 will never be the only supported version of Ubuntu.

Your wireless, sound, and GUI problems are probably not strongly related to each other. If you decide you want to work on fixing them, I recommend you post separate questions for each.

Separately from that, if you prefer the old interface from Ubuntu 10.10 Desktop Edition, you can select "Ubuntu Classic" as your session type when you log in (this setting is available after you have specified your username, while you're being asked for your password). This setting is remembered--you don't have to specify it each time you log in. You can also set it in the Login Screen preferences window.

Downgrading has never been supported in Ubuntu, and I am not aware of any other operating system of any kind that has ever supported downgrading an installation to an earlier release, though on Microsoft Windows it is sometimes possible to downgrade to an earlier service pack level of the same operating system. If downgrading were supported and you did it, the problems that started with the upgrade might be retained anyway (since they might be a result of configuration changes rather than software versions).

If you want to resume using Ubuntu 10.10, I recommend offloading all your documents and important files (e.g., music, videos) and then installing Ubuntu 10.10 (or 10.04, if you prefer that version). If Ubuntu 11.04 is currently the only operating system installed on your computer, you can just tell the installer (for Ubuntu 10.10 or Ubuntu 10.04) to use the entire disk, installing over the Ubuntu 11.04 system. On the other hand, if you have another operating system installed on the same drive (such as Microsoft Windows) and you want to keep it, you might be better off removing the Ubuntu 11.04 installation manually before running the Ubuntu installer. To do that, boot from the Ubuntu 10.10 or Ubuntu 10.04 install CD/DVD/USB, select Try Ubuntu (instead of Install Ubuntu), then when the desktop comes up go to System > Administration > GParted Partition Editor and remove the partitions associated with the Ubuntu 11.04 system. Then quit GParted, run the Ubuntu installer (by double-clicking on the Install Ubuntu icon on the desktop), and have it install Ubuntu in the available space on the drive which you just created. If you need help with this, feel free to post a new question.

Eliah:

That's not a very good attitude. How do you know the person didn't accidentally hit the wrong button. Your retort suggests an assumption of malice where alternatives exist and suggest you have some anger issues related to people who don't know as much about Linux/Ubuntu as you do. This only serves to drive people away.

Downgrading should be an option in a distribution that is so rife with problems (the blogosphere is awash with talk about how bad 11.04 is, not to mention "Unity"

I suggest that you guys have some serious issues with perspective. You have created Ubuntu to be the most user-friendly version, yet you guys are the least user-friendly support community I've ever come across. That doesn't sell Ubuntu very well. I no longer recommend it to my friends as a result of the problems I've had both with the software itself, and more importantly, the community.

Please, consider what you are saying and how it will be taken by those of us who aren't life-long linux experts like yourself. We don't have the knowledge and experience with Linux that you have. That does not make us idiots, which is precisely what your reply here suggests we are.

As for Ubuntu not supporting downgrading, with the problems of 11.04 as an excellent and fresh example, perhaps its time someone took the initiative to create a mechanism to do a clean downgrade as a mechanism to help users whose systems break in some way when they update or upgrade - like mine has, EVERY SINGLE TIME!

And whatever you do, don't read emotion into MY post where it does not exist. I am not upset, and in fact, feel quite sorry that you had to resort to anger in your reply. I want to help you and all Ubuntu experts have an easier time, and making the software work and making it so us "idiots" can work through problems more easily on our own - as in without having to resort to using this system or the forums - will not only make things easier for you as far as not having to keep telling us what to do, but will make us happier and more patient in dealing with the problems.

My intended solution to this problem - my upgrade to 11.04 ended in complete disaster - is to reinstall fresh as 10.04, if I can find it without the updates, so I can get back to using Twinview. If that doesn't work, I'll just install Fedora Core. Barring that, I'll probably just go back to the operating system I am most comfortable with: Windows 2000. The reason is this: if I have a problem upgrading every time, and every time I have a problem with an update or something else people tell me it is because I need to upgrade; then why would I continue to use this software if I can't find a stable version that will work forever? I require a stable operating system, period. And Ubuntu is not providing that. It is not an insult against anyone, it is merely a statement of facts from my own perspective. Ubuntu has proven to me it cannot meet my needs for a stable operating system. Due to the problems of installing fresh, I will try reinstalling 10.04 again to see if it gets me stable. If it does, I will never update or upgrade again, period, and will eventually try another distribution like Fedora Core. Barring that however; the only logical choice is Windows 2000. Ubuntu was an experiment to see if I could get away from the evil that is Windows. But sadly, Ubuntu and its community have not provided a solution and thus, I will likely have to call Linux a failure from the perspective of what I need in a computer operating system.

@Rex Beowulf
Perhaps you should read what I wrote, again. No part of my post was angry or mean, and I was not the least bit upset when I wrote it. My post was, in fact, quite dispassionate and technical, while still (I hope) being reasonably easy to understand for someone who is not experienced using Ubuntu.

"That's not a very good attitude. How do you know the person didn't accidentally hit the wrong button."

I don't. I didn't claim to know that, in my post. I didn't think I knew that, when I wrote it. What I did do was to politely explain the proper use of the different buttons. I did this because in my experience, it is more common for inexperienced Launchpad users to click the wrong button due to confusion about the way the buttons are meant to be used, that to know which button is appropriate, but click the wrong one by accident.

Nothing I said, in that part of my post or elsewhere in it, was accusatory or judgmental. Nothing I said was angry. I am quite astounded that you interpreted it that way.

"That does not make us idiots, which is precisely what your reply here suggests we are."

I do not think that people who are less experienced with Ubuntu than myself are idiots. I do not believe I have ever said anything, anywhere, that would suggest I think this. What is it that I said, that makes you think I think (or have ever thought) that?

"And whatever you do, don't read emotion into MY post where it does not exist."

I appreciate that, as you have said, the purpose of your post is not to express anger, in spite of the rudeness it contains (accusing me of emotional problems, and the use of screaming capitals). I would appreciate it if you would also understand that my post, to which you were responding, was not angry, especially considering that my post did not contain any indicators of anger. (This post is not angry, either.) I hope you are willing to hold yourself to the same standard to which you would hold me.

In your post, you put "idiots" in quotes, which seems to imply that someone on Launchpad called some person an idiot, or some group of people idiots. If someone did that, I am sorry to hear that. I myself did not do so--not in this question, and not in any other question. In fact, no one has used that word in this thread, until you did.

I agree with you that downgrading should be possible. Many things should be possible, but not all of them are, because they present significant technical challenges. Hopefully downgrading will be supported one day soon. You may be able to hasten that day by searching http://brainstorm.ubuntu.com for a current topic about downgrading, and contributing to it (or, if there isn't one, creating one yourself). As I said in my previous post, the ability to downgrade would not necessarily solve all problems caused by upgrading. But it would certainly solve some, and help in many situations. If someone works to develop downgradeability, I would certainly not think their efforts were in any way wasted.

You mentioned that you are planning to try reinstalling Ubuntu 10.04. I am not sure what you mean by "without the updates." It is currently recommended to install Ubuntu 10.04 using the 10.04.2 CD, which you can get at http://www.ubuntu.com/download/ubuntu/download (select "Ubuntu 10.04 LTS" under "Download options"). If for some reason you need the original Ubuntu 10.04 CD (before 10.04.1 and 10.04.2), I am not sure where you can get that now. You might want to post a new question (https://answers.launchpad.net/ubuntu/+source/ubiquity/+addquestion) about that; perhaps someone knows the answer. If you were to install from an original 10.04 CD and update your system (not to a newer release, just a normal software update), you would have the same system that you'd get if you installed from a 10.04.2 CD and updated. Furthermore, it is highly recommended to install at least security updates, so that your system is not vulnerable.

My goal in answering questions is not to get more people to use Ubuntu. It is to help people with their computer problems, and empower them as users. For some users and some applications, Ubuntu is not a good choice. The factors that contribute to deciding what operating system to use are numerous and complex. Ubuntu is not the only operating system I use, nor is it the only free, open source operating system I use. I have not used Fedora for some time, but my personal experiences with it, and what I've heard since, make me think it's a pretty good operating system for many users' needs (which is the same thing I think about Ubuntu). I think that Fedora is sometimes a better choice than Ubuntu, just as Ubuntu is sometimes a better choice than Fedora. There are many other operating systems to choose from (e.g., Debian, openSUSE, FreeBSD), which may sometimes be found preferable. I think Microsoft Windows is sometimes a better choice than Ubuntu (and other free, open source operating systems), too. I do not currently use Microsoft Windows, but I have used it extensively in the past (often alongside Ubuntu), and I will likely use it extensively again in the future, as I had done before.

I would caution you that Windows 2000 is no longer supported by Microsoft, so it no longer receives security updates. That probably makes it a poor choice for most applications, because security vulnerabilities continue to be discovered and publicized (and exploited). For the same reason, I would generally discourage people from using unsupported versions of Ubuntu or other free, open source operating systems (currently Ubuntu 10.04 LTS, 10.10, and 11.04 are supported, and Ubuntu 6.06 LTS Server and 8.04 LTS Server systems are supported, provided that they're not using desktop packages, such as those that provide or use a graphical user interface, and provided that they are not using packages from the universe and multiverse components). Microsoft Windows XP with Service Pack 3 is supported until April 2014 (http://www.informationweek.com/news/windows/operatingsystems/208800494), so if you're going to use Windows and want to use an older version that requires fewer system resources (and has less DRM) than the latest versions, you may want to look into that.

(By the way, as alluded to in that Information Week article, it seems that it's possible to downgrade Windows Vista to Windows XP, or at least to install XP over a Vista system in a way that works reliably, though doing so is a bit technical. I'm not sure if that goes beyond the limited ability to "downgrade" an Ubuntu installation to a previous release by installing the older release over the newer one and keeping /home--which, practically speaking, judging by posts I've read here on Launchpad, seems often to result in data loss if /home is not a separate partition. In any case, one point that could perhaps be made about downgrading Ubuntu is that, even if easy downgrading is unavailable--or before it is available--it would still be helpful to have an official, or community-contributed, guide to manually downgrading that applies to current versions of Ubuntu, if someone can come up with a workable technique.)

Whatever operating system you ultimately choose to use, I hope the problems you're experiencing are quickly resolved to your satisfaction.

Correction: "...that to know which button is appropriate, but click the wrong one by accident." --> "...*than* to know which button is appropriate, but click the wrong one by accident."

@Elijah Osborne
Well, this question has gone in several different directions since you originally posted it. Is your own problem now resolved? If not, do you want further help?