Hi I wondered if anyone has had a fix for this issue,

 

I am currently getting the same error, after creating my own page from the demo. 

I have installed the licence and configured the config file, everything works the first time round, also works if you add and then delete the uploaded attachment, however if you add more than one I get the invalid postback.

 

 

Any pointers would be appreciated.

I am running 2.0 Ajax uploader, and copied the example from the multi-files-upload example.