When using Scancat-Lite-Plus (SCL) on Windows 7 you may experience an error when trying to save an RSD file.
USUALLY no matter how many times you click in "Save", it just sits there and won't save it.

If you look closely, you will see the filename looks something like this
    sample.rsd.*txt

However trying to erase the *txt
and saving the file as "sample.rsd" will then produce the error
    "The Filename is not valid"

What is REALLY happening is Windows does not recognize the RSD file extension type,

The FIX is really simple.
You need to add the ''RSD'' extension to the "recognized file type list" in Windows.

FIRST WAY
RIGHT click on "START"
For Windows XP, WIN 7, WIN 8, WIN 10
Choose to open "Explore", (The File viewer)
   ONE simple way is to use "Search",
      and look for files and folders for "*.RSD" files
   Go to the Scancat folder to cut down on the Time used to find files
   When you locate an RSD file use "open with",
   and check the box to "use this all the time"

THEN - CHOOSE TO OPEN WITH ''SCANCAT''

SECOND
If that does work...

Go to TOOLS > FOLDER OPTIONS
Choose the "File types" Tab
At the bottom of the list of the file types,
choose "New"

http://www.sevenforums.com/tutorials/18212-index-add-remove-file-types.html

If you don't know how to do this,
Use the above link to view step by step instructions
   on how to add RSD or other filetypes to the "list" <ggg>