Very odd, eMail sender listed as _, plus more..

[zefyx]

So, something weird is happening, regardless of having my webmaster@example email in contact details, everytime someone is emailed from my forum the sender is listed as _. Also, when someone registers, at the top left hand corner of the navbar right above "Thank you, proceed to edit Profile, blah blah" it shows a white _. When I receive the New User emails, the referrer is listed as _, unless the user specified a username in that space.

Any ideas? This is quite annoying.

[Dismounted]

Is the "_" meant to denote a white-space, or an underscore itself?

[zefyx]

An underscore itself.

[Marco van Herwaarden]

Sounds like you have set your Site Name to "_".

[zefyx]

Nope, site name is perfectly fine within the admincp & for verification, it show's at the top of the web browsers title correctly as well.

[zefyx]

Any other ideas?

[snakes1100]

Did you try to disable the plugin system via vbulletin options and send out an email and see if the issue is gone?