Compose key on Windows

On Linux, the Compose key is a great way to enter many symbols. E.g.

em-dash — by pressing Compose then - - -
ö by pressing Compose then : o
Euro € by pressing Compose then C =

(The Compose key function can be assigned to various keyboard keys, such as right/left Alt, right/left Windows key.)

I really miss the Compose key when using Windows. I've looked but so far haven't found any way to get equivalent Compose key functionality on Windows. Does anyone know of how to do it?

Solution 1:

Though this is an old question, many others probably stumble upon it via a Google search. So about 4 years after it's been asked, I figured a few more options do exist. I couldn't test them all (at home I have no Windows but those for light and fresh air -- and at work I cannot access e.g. Dropbox to download the archives of some), but here's a short list:

AllChars: Last updated in 2009, but still seems to work up to Vista. Additionally offers "macros", which one cannot disable or edit on Vista, so the pre-defined ones might get in your way (not that likely, but they might). Update: After having used it for a while, I encountered some strange effects I attribute to this app (as they didn't happen before I installed it). No pattern in regularity, but sometimes my keyboard seemed to be messed up, CAPS inverted, some keys not working. Might be something else, though – but I didn't have that before. Update 2: None of the side-effects encountered since I switched to...
WinCompose: No extra gimmicks like macros or the like, but that's not what we're looking for here :) Seems to use the very same layout I'm used to on Linux. Need some longer testing, but after one day it's already my favorite candidate here. Edit: Half a year later, it's still my favorite. Easy to install, runs stable, no side-effects, simply great! Update: Reportedly works from Vista to Win10. Still happy with it 3.5 years later :)
CKFW: Compose Key For Windows. Couldn't test it as I couldn't access Dropbox for download.
Unichars: I didn't test it due to the restrictions listed in this blog (doesn't work with all programs).
FreeCompose: Last release in 2011, though the dev claims it's still alive in the repos. It's supposed to work with most programs (PuTTY had trouble, but a patch is provided). Disadvantages: annoying beep when "composing", which cannot be switched off. Also compose sequences are not the standard ones. Advantages: You can define your own sequences, and the service can be de-activated while running (without exiting it).
USCompose is an alternative US keyboard layout, including some compose stuff. Not always matching the Linux compose key sequences.
Accent Composer: commercial; demo available. Not tried.
Compose-Keys: Claims to mimic the Linux compose key sequences (I missed a few, and not all of them seemed to work; sometimes one simply needs to "try until they do". Well, I have the same issue on Linux sometimes ;) Freely available at GitHub.
WebComposeKey: browser-based, cross-platform. Nice to learn what sequences are available :)
DIY: Microsoft Keyboard Layout Creator

This should give anyone in need a few additional options. I wonder if MS will finally built this functionality into their releases, where it belongs (note the "if", not "when")...

Solution 2:

There are a couple of utilities to emulate the Unix-a-like key composition chords under windows. Allchars is one, which is also F+OSS, though I've not actually tried it myself yet (it is one of the many utilities in my "to try later" bookmark folder).

Solution 3:

On Windows, AllChars should do what you want. I have been using it for the exact purpose you describe for almost a year now.

Caveat: If you install AllChars and your keyboard starts to behave weirdly, try one of the other versions they offer, possibly the alpha/beta. They all seem to have different issues with the different versions of Windows out there. But one of them should work with whatever you use.

Solution 4:

There's also Freecompose, found on code.google.com, but it has that annoying beep everytime you start compose mode.

Solution 5:

Accent Composer looks promising, and I hope to try it some time.

Update:
Actually AllChars seems to do what I need (despite the web site saying it doesn't; I guess the web site's info is out-of-date compared to the latest version), and it's free. So I won't bother with Accent Composer.