the mark of analysis

I just figured out the solution to a problem I noticed.

Tonight I went to rename picture files on my SD card. I do this
frequently by using a little renaming script I created with "A Better
Finder Rename 7." Typically, I open the SD card folder, locate the
pictures, highlight them, drag them onto the script, and it renames
them thusly: yymmdd hhmmss pic#.jpg

Then I move them into folders based on date (such as 0911, which
would be today) and move THOSE to a folder on the hard drive. Then I
wipe the SD card clean.

Tonight, however, it kept telling me that I hadn't the permissions.
My first thought of course was that the card was locked. But