I am really tearing out my hair on this one. I have a flex project using Flash Builder 4.5.1 that uses BlazeDS remoting services.
I run my Flash Builder inside a Oracle VirtualBox VM (Windows XP) since I am an Ubuntu user. I have been happily compiling and deploying for a couple of months without any hassles.
Recently I got a new laptop. I exported my VM, and imported it on the new laptop. Suddenly my project upon compilation gives me an error: "The parameter is incorrect" location "Unknown".
If I create a simple project from scratch it compiles fine without any problem. I can then navigate to my BlazeDS service, add it - but as soon as I make a reference to that service in my component - the component compiles fine but on project level it gives the above error.
I have been searching everywhere for a more verbose version of the error - but nothing.
So for those interested, I solved this problem by creating another blank Windows VM, re-installing Flash Builder and importing my project again.
It seems that Adobe Flash Builder has built in something obscure that does not like you migrating a VM to another host. I did un-register and re-register my product between the VM's by the way - that also did not work.