Windows NT does not provide keyboard support in the MS-DOS sub-system for:

Albania
Ukrainia
Belarussia
Slovenia
Estonia
Latvia
Lithuania
Serbia (Cyrillic)
Polish (Regular keyboard, the Polish Programmers keyboard is supported)
To add support for these keyboards, you must acquire MS-DOS files to replace Keyboard.sys and a full-screen font to replace Ega.cpi. The Estonian keyboards file can be found at ftp://ftp.itedu.ee/microsoft/windows9x/windows_95/updates/addest11.exe

The Estonian full-screen font is Ega3.cpi and is available with the Pan European version of Windows 95. The following table gives you the font file names for other countries:

Country Font File File Name
------------------------------------------
Albania Ega.cpi Third-party
Ukrainia Ega3.cpi Keybrd3.sys
Belarussia Ega3.cpi Keybrd3.sys
Slovenia Ega.cpi Keybrd2.sys
Estonia Ega3.cpi See ftp site above
Latvia Ega3.cpi Third-party
Lithuania Ega3.cpi Third-party
Serbia (Cyrillic) Ega3.cpi Keybrd2.sys
Polish (Regular) Ega.cpi Keyboard.sys
Once you located the required files: ( Don't ask me where to find them, If I knew, I would have listed the location.)

1. Use Regedt32 to locate your keyboard at
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layouts
    The Estonian keyboard is 00000425.

2. Locate the above at:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout\DosKeybCodes
    Replace us with the two-letter code for your keyboard (in the keyboard description documentation).
    Estonia is ee.

3. In Control Panel / Regional Settings / Regional Settings tab, make sure your country is set as the system default.
    If you set it now, do NOT reboot.

4. In Control Panel / Keyboard / General tab, make sure your keyboard is selected
    and on the Input Locale tab, it is the default.

5. Rename %systemroot%\system32\Keyboard.sys to Keyboard.old.

6. Use Mv.exe - Posix or an alternate boot of NT to rename
    %systemroot%\system32\Ega.cpi to EGA.CPI.SAVE. If using Mv.exe:
    MV /x /d EGA.CPI EGA.CPI.SAVE

7. Place the new CPI file in the %systemroot%\system32 folder:
    MV /x /d EGA3.CPI EGA.CPI

8. Restart.

NOTE: You can skip step 6 and 7 if you don't need full-screen support for MS-DOS on an Intel platform. Be sure to use a True Type font for the display as trhe bitmap font doesn't contain the characters you need.