Hi,
My store has suddenly caused me some trouble. This is happening just to logged in users. If you are not logged in it works fine. A logged in user gets a totally white screen(entire template, menu, ect goes away) with a single black dot at the top left. I am running 3.0.8 on joomla 2.5.28 which is the latest version the host allows to be installed. I am not getting any errors in the logs. Nothing coming up when I enable debugging. I was running on 3.0.6 and it was doing the same thing, after the upgrade same. I have copied a copy of the virtuemart.php from a working site in and no change.
Any ideas?
Normally an error like this is logged somewhere - have you asked your host?
On a shared environment often only they have access to the apache logs for example
In the worst case with problems like this I take a copy and install it locally on xampp etc - at least then u have full access to everything