"Invalid output file name" problem

Hi

I have installed FMLE in a Windows Vista Home Premium SP2 x64 machine. When I run the GUI version with any preset (using Medium bandwidth 300kbps VP6) and selecting "Save to file" "C:\temp\sample.flv" I get this error:

Invalid output file name

Filename cannot be invalid and absolute path of the file cannot exceed 255 characters.

The folder C:\temp DOES exist. I am running from my administrator (only) account. FMLE works just fine in my Mac but for some reason I need to set up a Windows machine.

What can be wrong?

Thanks