If you receive the error "There was an error creating the child process for this terminal" when trying to open a terminal window in GNOME, it means that the terminal emulator was unable to start a new shell process. This can be caused by a variety of issues, including incorrect permissions on the shell executable, issues with the system's environment variables, or problems with the terminal emulator itself.
Here are some steps you can try to troubleshoot and resolve this issue:
Check the permissions on the shell executable: Make sure that the user has permission to execute the shell executable (e.g. /bin/bash). You can check the permissions on the shell executable by running the ls -l command and looking for the x permission.
Check the system's environment variables: Make sure that the SHELL and PATH environment variables are set correctly. You can check the value of these variables by running the echo $SHELL and echo $PATH commands.
Check for missing or corrupt libraries: Make sure that all the libraries that the terminal emulator depends on are present and not corrupted. You can use the ldd command to check for missing or corrupt libraries.
Try starting the terminal emulator with a different shell: If the issue is with the shell itself, you may be able to start the terminal emulator with a different shell. For example, you can try starting the terminal emulator with /bin/sh instead of /bin/bash.
Reinstall the terminal emulator: If none of the above steps help, you may need to reinstall the terminal emulator. This will overwrite any corrupt files and may fix the issue.