After over three decades of Microsoft Windows success, there have been some clear failures along the way. With that in mind, we’ve picked the six worst versions of Windows. All of these made us want to stick to older, better versions of Windows, or use alternatives like Macs or Linux instead.

In developing this list, we considered the following metrics: How much people hated each version (appearances on other worst-of lists), how poorly it sold, how slowly it was adopted, how bad its reviews were, the length of its lifespan on the market, and our own personal experiences with the software. For fun, we also googled “Windows [x] Sucks,” and tallied up the results.

Honestly, there’s no hard science to this, so you might not agree with our exact ranking, but we can confidently predict this: If you ran at least one of these versions of Windows, you wanted to upgrade.

For simplicity’s sake, we’re going to stick to full desktop versions of Windows (with the slight exception of an ARM-based detour), so more obscure server and PDA releases will be spared humiliation (for now).

Windows 1.0 might rank high in terms of importance (for, well, being the first-ever version of Windows), but it was a stinker in the marketplace. Unlike Macs that were built from the ground-up with hardware optimized to use a mouse-and-GUI interface, IBM PCs had to rely on kludgy software tricks to even begin to approach doing the same thing.

As a result, Windows 1.0 pushed the limits of a typical 1985 PC’s capabilities at the time, making it a memory hog that was too slow to use. In 1986, The New York Times reviewed Windows 1.0 and wrote that “running Windows on a PC with 512K of memory is akin to pouring molasses in the Arctic.” Add in poor third-party support, and you had a true dud.

Luckily for Microsoft, things got better: The average PC became powerful enough to handle Windows smoothly by the early 1990s.

RELATED: 35 Years of Microsoft Windows: Remembering Windows 1.0

#5: Windows XP (Initial Release, 2001)

Sure, after all the fixes, Windows XP was one of the greatest versions of Windows of all time. But some of you might remember what XP was like before 2004’s Service Pack 2 release: a buggy mess with driver problems and huge security holes.

There were also growing pains for Windows XP’s brand new activation system, which was a first in Windows at the time. To prevent piracy, Microsoft required customers who built their own machines or upgraded to activate their copy of Windows XP over the internet or by telephone. If you made significant changes to your computer’s hardware (such as installing a new hard drive or graphics card), Windows XP would require reactivation, which caused no shortage of headaches for some people in an era when always-on internet wasn’t a given.

Luckily, Microsoft continued to refine XP for years, and it eventually became a solid, stable OS that many were hesitant to give up. The release of Windows XP Service Pack 2 was a pivotal moment that made the operating system much more secure.

RELATED: Windows XP Users: Here Are Your Upgrade Options

#4: Windows RT (2012)

Microsoft crafted Windows RT as an ARM-based version of Windows that would run on a new class of lighter, more power-efficient machines like the Surface RT. There was only one problem: It couldn’t run millions of Windows apps designed for Windows’ traditional x86 architecture. And most of the Windows 8-specific apps in the Windows Store at the time weren’t very good.

Even worse, it teased full desktop support with a desktop mode that would only allow Microsoft desktop apps such as Microsoft Office. Third-party apps were forbidden, even if recompiled for ARM. In the end, RT was more than just an embarrassment: The failure of Windows RT and the accompanying Surface RT hardware led to a $900 million loss for Microsoft in 2013.

RELATED: What Is Windows RT, and How Is It Different from Windows 8?

#3: Windows 8 (2012)

Windows 8 was a daring business move on Microsoft’s part. It saw the challenge to PCs posed by Apple’s iPhone and iPad (year-over-year PC sales began to drop in 2011) and decided to tackle it head-on with a crossover OS that could handle both touchscreens and desktop PCs.

Unfortunately, Microsoft got a little too enthusiastic with its new strategy, forcing its core customer base of desktop PC users to compromise their productivity for a new touchscreen-first interface called Metro. It was a great interface for tablets, but not for desktops.

In fact, Windows 8 treated the desktop windows experience as an afterthought: The OS booted into the Start screen by default and hid the “Desktop” behind an icon. Once you got to the desktop, there was no Start menu, and there were annoying hot corners. If you left your mouse in the upper-right corner of the screen for a moment, a Charms bar would pop up.

Ultimately, Windows 8 was an all-out bet on mobile-first that didn’t pay off. The reviews for it were dismal, and Microsoft backpedaled hard, first with Windows 8.1, and then with Windows 10. Throughout, many users simply stuck with Windows 7 or even jumped ship to Macs.

RELATED: Why I Still Use Windows 7 After a Year of Trying to Like Windows 8

#2: Windows Vista (2006)

After the great success of Windows XP, Windows Vista was a fiasco. The shiny new OS came in six confusing editions (Starter, Home Basic, Home Premium, Business, Enterprise, and Ultimate), dicing the market into a salad and confusing customers.

One of the earliest complaints about Vista was that it ran sluggishly on machines that performed very well with XP. It was also a memory hog. This was partly thanks to its flashy new translucent Aero interface and always-running gadgets, which taxed graphics capabilities, memory, and CPU power.

Then there were puzzling annoyances that had been meant to help, but that actually just got in the way. Case in point: The dreaded User Account Control (UAC) prompts that would pop up every few minutes to cover the screen whenever you actually tried to do something with your computer. Luckily, it was possible to turn them off with some tinkering, but what was Microsoft thinking?

In the end, we can thank Vista’s plentiful failures for the glory of Windows 7, which fixed Vista’s problems while retaining its advancements.

RELATED: 4 Ways to Make UAC Less Annoying on Windows 7 / Vista

#1: Windows Millennium Edition (2000)

Initially, Microsoft meant for Windows 98 to be the last OS based on the legacy MS-DOS kernel, but the firm realized that it didn’t have time to finish preparing an NT-based Windows for consumers. The result was Windows Millennium Edition, or “Windows Me” for short.

What was wrong with Windows Me? Well, chief among the problems was that many people found that it crashed—and it crashed a lot. To our knowledge, no one has ever explained exactly why Me was more unstable than the already unstable Windows 98, but we suspect that it was due to bugs that were introduced when Microsoft hastily added new features to Me without proper testing.

There were other issues, too: Programs running on Me tended to produce lots of memory leaks, which could cause crashes as well. The included System Restore utility didn’t work properly at first. And Me removed MS-DOS Real mode, which was necessary for some legacy programs to work, especially late-era MS-DOS games from the mid-1990s, which many PC users still played at the time.

To add insult to injury, Microsoft already had the answer up its sleeve: Windows 2000, which was stable and glorious. Sure, it lacked the flashy consumer bells and whistles, but it could have done the trick. Instead, Microsoft punted the ball with Me, and only began to rebound with Windows XP in 2001 (which initially had its own share of problems, as we covered above).

RELATED: Windows Me, 20 Years Later: Was It Really That Bad?

Honorable Mention: Windows 10 (2015)

It’s been a rough road for Windows 10. Among its problems: built-in advertising, freemium games, forced updates, data collection and privacy issues, and a Frankenstein look-and-feel that merges bits and pieces of four generations of Windows into one product, which Microsoft is still working on refining.

Windows 10 gets high marks for offering a competent desktop experience, but it somehow does touchscreen worse than Windows 8. And speaking of Windows 8, Microsoft straddles two software architectures: UWP and the legacy Win32 platform. Torn between wanting to ditch legacy Win32 apps—which Windows 10 runs poorly in high DPI modes—but keep its massive install base, Windows 10 is neither here nor there.

With Windows 10, the sometimes inscrutable updates never end. Microsoft continuously fiddles with new features, turning them off and on while orphaning apps and utilities. And there are still at least two different ways (Control Panel and Settings) to configure the system. Windows 10 feels like pieces of code bolted on here and there, with no grand vision uniting them.

We’ve gotten enough comments about Windows 10 over the years to know that many people really, really don’t like many aspects of it.

So even though Windows 10 is one of the greatest versions of Windows of all time in many ways, a strong case could be made that it’s also one of the worst in other ways. If there’s ever a Windows 11, let’s hope that it can get a fresh start without breaking everything (like Vista and Windows 8 before it). The future awaits!

RELATED: How to Disable All of Windows 10’s Built-in Advertising