Hello,
Did you edit the logs ?
file:///C:/Users/user123\AppData\Local\Programs\balena-etcher\resources\app\generated\index.html
The slash (not antislash) before user123
looks out of place.
Is this file available on your computer ?
Is there anything running that could prevent etcher from accessing it ?
I remember having issues on Windows 7 when the Visual C++ redistributable was not installed, you can get it from here https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads .