Heres another procedure which tends to fix java-related errors...
This is the same procedure for Windows XP, vista and Windows 7:
go to the windows control panel, double click on 'Java'
near the bottom-left theres a 'View..." button, click that, on the
window that opens, click 'satscape' in the list, then click the red
cross at the top of the window. Repeat this if you have another
'Satscape' in the list.
On the top-right where it says "Show : Applications" click the drop-
down list and change it to 'Resources'
if you see 'Satscape.jnlp' in that list, click that and click the red
cross.
This will clear out the java cache, forcing your PC to go get new
copies of the files.
Finally click this link :
http://www.satscape.info/java/satscape/Satscape.jnlp
to install a fresh copy (this is the same link as the web site
download link)
Mac users: Spotlight > "Java preferences" will get you into the same
place mentioned above.