I tried to reproduce the issue locally but to no avail, it all seems to work fine.
Connecting to Sitefinity from both Thunder and Sitefinity Desktop Application (previously known as Lightning) using smith&wesson
for both username and password was successful.
To move forward can you tell me what is the thunder version currently used?
What is the version of Sitefinity do you try to connect? If there is an error message generated by thunder as a result of the usage of any operation please make sure to update thunder to the latest version from Tools->Extensions and Updates->Visual studio gallery (inside visual studio).
This way we would be able to further investigate the behavior your experience.
Thank you in advance.
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