Our ISP have informed us that they came under sustained attacked yesterday from a particularly nasty virus. They have discovered how the virus propagated and can say for sure that this was a malicious virus spreading exercise, not concerned with data retrieval.
This virus plants itself in the users browser and uploads to a server when they submit data via a form. Once on the server it runs a script and corrupts all data from within the database.
Although not directly related to our site or users we would strongly recommend that you run a full virus scan on your machines to make sure that you are not carrying this virus.
Unfortunately we have had to restore data back to 2am on Wednesday morning, so any changes between 2am and 6pm have been lost, for which we apologise. Our ISP have discovered which site and pages that were being targeted, have traced it back to specific times and procedures used. We have implement some security measures that should stop to this happening again.
Once again we apologise for any inconvenience cause.

facile est inventis addere.
it is easy to add to things already invented.