Steps to reproduce:

1. Start NVDA 2019.3 beta 1.
2. Create a portable copy.
3. When asked where to create the portable copy, specify a folder name which includes a character such as é, ç, ş, ğ.
4. Start the portable version.
5. Open NVDA's synthesizer dialog (NVDA+control+g)
6. Press HOME or use the arrow keys to select the "eSpeak NG" synthesizer.
7. Press ENTER.

Actual behavior:

At the last step, NVDA immediately stops running (visually, the icon stays in the system tray until you mouse over it, that's simply an artifact of Windows not cleaning up properly - NVDA is not running by this point).

The very last entry in my NVDA log at Debug level is:

IO - inputCore.InputManager.executeGesture (13:03:39.817) - winInputHook (17464):
Input: kb(desktop):enter

(Registering the ENTER key being pressed to activate the OK button, set the synthesizer and close the synthesizer dialog.)

Expected behavior:

Synthesizer should switch to eSpeak NG and NVDA should continue working normally.

System configuration

NVDA installed/portable/running from source:

Portable, and setup in a folder which includes an accented character such as é, ç, ş, ğ

NVDA version:

2019.3 beta 1 (which uses eSpeak NG 1.51-dev, commit ca65812ac6019926f2fbd7f12c92d7edd3701e0c).

Windows version:

Windows 10 Version:
18362.388

Name and version of other software in use when reproducing the issue:

Other information about your system:

Other questions

Does the issue still occur after restarting your PC?

Yes

Have you tried any other versions of NVDA? If so, please report their behaviors.

Yes, 2019.2.1 works fine in this situation.

Issue also filed with eSpeak NG as their issue 692: espeak-ng/espeak-ng#692