So on new OS, verification is OK and I can login, no errors yet, this was 1.5.0.0 (un patched)
I then updated to latest version and this happens:
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So to pin down which update it starts happening, I uninstalled PR, checked login process after manually applying each update. Verification and login was success up until 1.5.4.4.
Only after applying 1.5.4.4_to_1.5.4.5 does it fail but at least its not verification.
An observable difference with this error compared the previous one is that it happens almost instantly after Play is clicked. Previous verification error occurred after few seconds.
Google: the i/o operation has been aborted because of either a thread exit or an application request
Mats has assured me that nothing has changed in _1.5.4.5.
I lost count how many times I've reinstalled PR and OS now