Korean Han/Eng Key Not Working? Windows Korean IME Troubleshooter
Step-by-step fix when the Korean/English Han/Eng toggle stops working
Typing Korean on Windows and suddenly the Korean/English (Han/Eng) toggle stopped working? This walks you through the likely causes one by one. No technical knowledge needed—just press the keys and pick the buttons as prompted. Everything runs inside this browser; nothing is sent to a server.
⚠️ This troubleshooter is for Windows computers. This device looks like a different system. You can still follow along below.
1
Check your computer
🖥️ Checking…
2
Press the Han/Eng key
🎹 Press the highlighted key once on your keyboard. On Korean keyboards it's usually just right of the spacebar, labeled 한/영 (Han/Eng). The Hanja key (한자) is often left of the spacebar.
Press the Han/Eng key now
3
Check whether Korean typing works
⌨️ Click the box below, then slowly type 다라마 (on a Korean layout: E, K, F, K, A, K). Switch to Korean mode first with the Han/Eng key, then type.
What happened when you typed?
4
Just a few questions
Does Korean/English switching also fail in other apps like Notepad or your messenger?
Did you recently install a Windows update, or did the computer restart on its own?
Did you recently connect this keyboard? (especially an international, mechanical or compact one)
When you press Han/Eng, does an indicator like ‘한’ / ‘A’briefly pop up somewhere on screen?
✓
Diagnosis — try these in order
⚠️ Only edit the registry (regedit) if you know what you're doing. If you're unsure, use the Copy button above and share the results with someone who can help or a repair shop. Most cases are fixed by restarting or setting up Right Alt.
⌨️ This keyboard has no dedicated Han/Eng key
Most non-Korean, mechanical, tenkeyless and compact keyboards have no Han/Eng or Hanja key at all. In that case, remap Right Alt to work as the Han/Eng key.
Search for “PowerToys download” and install PowerToys (free) from Microsoft's official page.
Open PowerToys and turn on Keyboard Manager in the left menu.
Click Remap a key → Add key remapping.
On the left (physical key) choose Right Alt; on the right (mapped to) choose Hangul.
If you also need Hanja, add another mapping the same way: Right Ctrl → Hanja.
Click OK at the top right. Right Alt is now your Han/Eng key.
Some keyboards have their own toggle such as Fn + Space—check the product manual too.
🔄 The input method (IME) is temporarily stuck (common after updates)
The Korean IME often gets tangled after a Windows update or a long sleep. A restart usually fixes it.
First, fully shut down and restart the computer. This alone fixes it most of the time.
If not, try Left Shift + Space to see if that switches (it's one of the default toggle keys).
Right-click the ‘한’ or ‘A’ indicator next to the clock at the bottom right and see whether a menu appears.
Go to Start → Settings → Time & language → Language & region. Click ⋯ next to Korean → Language options → ⋯ next to Microsoft IME → Keyboard options → turn on Use previous version of Microsoft IME.
After changing settings, restart again or sign out and back in.
🧩 The background service that handles Korean input has stopped
If Windows' text input service (ctfmon) stops, pressing Han/Eng does nothing at all.
Restart the computer. That brings the service back in most cases.
If it still fails: press [Windows key] + [R], type ctfmon in the small box and click OK. No window appears, but the input service restarts.
If it keeps happening: in Settings → Time & language → Typing → Advanced keyboard settings, toggle Use the desktop language bar when it's available.
🔧 Windows has misidentified your keyboard type
If Han/Eng behaves like Hanja (or vice versa), Windows has detected your keyboard as a different type (e.g. 101-key vs. 103-key Korean).
First, restart. Windows re-detects the keyboard and this sometimes fixes it.
Connecting a genuine Korean keyboard via USB (with real Han/Eng and Hanja keys) usually gets detected correctly.
If it's still wrong, the keyboard driver setting (registry value LayerDriver KOR) needs changing. This is risky to edit by hand, so use Copy results above and ask someone knowledgeable or a repair shop to “check whether the keyboard type (101/103-key) is detected correctly.”
🌐 It works elsewhere but not in this browser
Han/Eng works in Notepad and other apps but not in your web browser (Chrome, Edge, etc.). Refreshing the browser usually fixes this.
Close the browser completely and reopen it. (If you have several windows open, close them all.)
Open Notepad, toggle Han/Eng there once, then return to the browser.
Update your browser to the latest version.
In Chrome, go to chrome://settings/system, toggle Use graphics acceleration when available off and on, then relaunch.
🔌 The Han/Eng key itself doesn't seem to register
The Han/Eng key may be physically broken. Comparing with another keyboard confirms it quickly.
Open our Keyboard Tester and press Han/Eng to see whether it lights up. If it doesn't, the key is broken.
Connect another keyboard via USB and press the same key. If it works on the new one, the original keyboard is faulty.
On a laptop, use an external keyboard for now or contact a repair service.
Workaround: as in “This keyboard has no dedicated Han/Eng key”, you can remap Right Alt as Han/Eng.
🗣️ The Korean input method isn't installed
If Korean characters never compose, the Korean IME (Microsoft IME) may not be installed in Windows.
Go to Start → Settings → Time & language → Language & region.
If Korean isn't in the list, click Add a language and add Korean.
Click ⋯ next to Korean → Language options → check that Microsoft IME is under Keyboards; if not, add it with Add a keyboard.
Switch the input language to Korean from the bottom-right of the taskbar, or press [Windows key] + [Space].
Restart after setup to be sure.
Working…
0.0s
It hasn't frozen — the result will appear when the calculation finishes.
About Korean Han/Eng Key Not Working? Windows Korean IME Troubleshooter
This is a troubleshooter for Windows PCs where switching between Korean and English with the Han/Eng (한/영) key suddenly stops working. It records what your browser receives when you press the key, checks whether typing 다라마 actually produces Korean syllables, and asks four questions — does it fail in other programs too, was there a recent Windows update, is the keyboard new, does a 한/A indicator flash on screen. From that it ranks three or four likely causes, each with steps to try.
It is not a converter that turns text typed in the wrong mode (such as dkssud) back into Korean. It looks for the reason the switch fails. A browser cannot see the registry or the list of installed input methods, so the result is an ordered list of things to try first, not a definitive diagnosis.
What the browser sees when you press Han/Eng
The W3C UI Events specification gives the Korean Han/Eng key the code "Lang1" and the Hanja key the code "Lang2". Some browsers report them instead through the key value (HangulMode, HanjaMode) or legacy keyCodes 21 and 25, so the tool accepts any of these.
The verdict splits like this. If Lang1 arrives, the keyboard and driver are fine and the problem lies with the input method editor (IME). If the key registers as Lang2 (Hanja), Windows has most likely misidentified the keyboard type. If it registers as Right Alt, the keyboard has no dedicated Han/Eng key there, or Right Alt is not set up to toggle. A keyCode of 229 (key value "Process") means the IME grabbed the key first — evidence that the key itself works.
No signal at all is the ambiguous case: Windows may have consumed the key before the browser saw it, which can be normal, or the key may be physically dead. The follow-up questions decide which is more likely.
Keyboards without a Han/Eng key
US and other international layouts, and many mechanical and compact keyboards, have no Han/Eng or Hanja key. Microsoft's documentation says the Korean IME also toggles with Right Alt and converts to Hanja with Right Ctrl, but whether that works depends on how Windows has classified the keyboard. When it doesn't, the tool walks you through Microsoft's free PowerToys Keyboard Manager to remap Right Alt to the Hangul key — much easier to undo than a registry edit.
Shift+Space is also recognised as a toggle, but it is an alternative; if your keyboard has a dedicated Han/Eng key, test that one too.
"Only English letters appear": how the 2-set layout maps
The standard Korean layout, dubeolsik (2-set), puts consonants under the left hand and vowels under the right. Type Korean while the IME is stuck in English mode and you get a predictable string of Latin letters: 안녕 (hello) is ㅇ-ㅏ-ㄴ-ㄴ-ㅕ-ㅇ on D-K-S-S-U-D, so it comes out as dkssud, and 한글 comes out as gksrmf. The doubled consonants ㄲ ㄸ ㅃ ㅆ ㅉ and the vowels ㅒ ㅖ sit on Shift + Q, W, E, R, T, O and P.
The tool's typing test uses the same idea. In Korean mode, E-K-F-K-A-K gives 다라마; in English mode it gives ekfkak. The box detects Korean syllables or jamo, or an IME composition event, automatically.
If you are learning Korean on an English-language Windows install, the most common causes are simpler: Korean has not been added as a language, or you are toggling between keyboard layouts with Windows+Space without switching the IME's own A/가 mode. The "not installed" result covers the first; the A/가 icon in the system tray shows the second.
The first thing to try for each cause
The tool chooses among seven causes. A restart and a Right Alt remap fix most cases.
IME glitch (common after updates): full restart, then turn on "Use previous version of Microsoft IME" in the Korean keyboard options.
Text input service stopped: restart; if that fails, run ctfmon from Win+R.
No Han/Eng key: PowerToys Keyboard Manager, Right Alt → Hangul.
Keyboard type misdetected (101-key vs 103-key): restart, or connect a genuine Korean keyboard. Leave the registry fix (LayerDriver KOR) to someone experienced.
Only this browser: close every browser window, reopen, update.
Dead key: test the same key on another keyboard.
Korean IME not installed: Settings → Time & language → Language & region → Add a language → Korean.
Worked examples
Broke right after an update
Input
Key test: Lang1 detected · typing test: English only (ekfkak) · fails everywhere · recent update: yes
Output
1st: IME glitch · 2nd: text input service stopped
Because the key signal reaches the browser, keyboard and driver causes are scored down; the update answer pushes IME causes up.
A new mechanical keyboard
Input
Key test: Right Alt · new keyboard: yes · no 한/A indicator
Output
1st: no dedicated Han/Eng key (remap Right Alt)
Pressing Right Alt without a switch means that key is not mapped to Hangul.
Works in Notepad, not here
Input
Key test: Lang1 · works in other programs
Output
1st: problem only in this browser
If switching works elsewhere, the browser's state is a better suspect than the Windows IME.
How to use it
Press the Han/Eng key once, or click "I can't find a Han/Eng key".
Type 다라마 in the box and choose what happened.
Answer the four questions ("not sure" is fine).
Try the fixes in order, and copy the report if you want to send it to someone helping you.
Frequently asked questions
Can it convert text I typed in the wrong mode, like dkssud?
No. This is a diagnostic tool for a broken Korean/English switch. Once switching works, the text needs to be typed again.
Does it work on a Mac?
The diagnosis is written for Windows. On a Mac you will see a warning; only the key test is meaningful there.
Do I need to edit the registry?
Usually not. A restart, the previous-version IME option or a PowerToys remap solve most cases. For the keyboard-type issue that does need the registry, copy the report and show it to someone experienced.
Can I send the result to someone?
Yes. The copy button produces a plain-text report with your system, test results, answers and step-by-step fixes.