Exact same error with 1.7.0. I used chocalatey to get 1.6.25 and everything was perfect. So this is a genuine issue.

From the old issue:
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Can't access to gitlab repo

error: unable to read askpass response from 'C:\Program Files (x86)\Atlassian\SourceTree\Askpass.exe'

bash: /dev/tty: No such device or address

error: failed to execute prompt script (exit code 1)

Completed with errors, see above.
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