AkelPad

Hello,
I am pasting/opening a Latvian text into Akelpad and I see many blocks [] or ? showing not recognized characters. This does not happen in Word, Blockpad, etc., just in AkelPad.
How may I fix this?

What is the AkelPad version you are using (version number and bitness: 32-bit or 64-bit)? And what is the Windows version (version number, build number and bitness: 32-bit or 64-bit)?

Hello, I am using Akelpad 4.9.8 x86 (that is 32 bits)
My windows is Windows 11 64 bits, updated to the latest update
I would appreciate how may I configure AkelPad to show also the latvian characters

I'm using AkelPad 4.9.9 dev, also 32-bit. It can be downloaded here:
http://akelpad.sourceforge.net/files/AkelPad.zip
http://akelpad.sourceforge.net/files/AkelPad-x64.zip

Tried under Windows 10 and Windows 11 with a sample text from this page, everything is good, no problems:
https://mylanguages.org/latvian_reading.php

There can be two possible reasons of having square symbols instead of proper characters:
1) A font that does not support these characters is used. I briefly checked with Courier New, Lucida Console and Liberation Mono - looks OK.
2) A file was saved with ANSI encoding and the characters unique for Latvian have been lost as the result. To be on a safe side, use either UTF-8 or UTF-16 LE encoding.

There can be another potential reason: the files with Latvian text you are trying to open were originally created using ANSI encoding (i.e. one byte per character) and your Windows uses non-Baltic locale. In such case, AkelPad can incorrectly detect the file encoding. To fix this case, you can right-click AkelPad's status bar (at the bottom of the window) in the part which shows the current encoding:

And select the proper encoding under Open As.
If that helps, you can go to Options -> Settings -> General where you may disable the Codepage recognition and/or set the Default codepage. (Note: "codepage" has the same meaning as "encoding").

You solved the problem, I tried also Liberation Mono and now Akelpad shows everything all right.

The version 4.9.9 is not for general public? I do not see it in the download page.

The version 4.9.9 is still "unofficial", even though it's already more stable than 4.9.8. In fact, this 4.9.9 "development version" has been collecting all the fixes for issues identified since the 4.9.8 official release, plus there were new enhancements added.