We're still learning about this message, but the following solution has proven helpful to some users.
The problem appears to happen if the default "My Documents" folder doesn't exist or has been moved/renamed. You don't have to store your reading plans in this folder, but apparently the reading plan wants to be able to find the default My Documents folder.
Solution for Windows Vista
Make sure PC Study Bible is closed.
You need to create the following folder on your computer:
But your folder will use your Vista "user name" instead of "tsmith".
To find out the value you should use instead of "tsmith"...
Right-click on your Start button and left-click on Explore
This should open Windows Explorer to some folder that is several levels down inside your C:\Users folder.
Read up the screen until you reach the Users folder.
Now read down until you reach a folder that is open, i.e. it has a *black* triangle in front of it.
This open folder is most likely the "user name" that you'll need to use.
Left-click on the user name ("tsmith" in our example)
In the right-hand panel of the screen,
right-click on a blank area
left-click on New
left-click on Folder
Set the name of the New Folder to Documents
Close the windows.
Now open PC Study Bible and try Tools > Bible Reading Plan again.
Solution for Windows XP
This solution is under construction.