When I try to move an icon, it just smoothly glides back to where I dragged it from. Sometimes though, after I've been logged on for a while, I can move icons and they'll stay where I put them. (I have no idea what changes this behavior.)

But the next time I log in, they're back to the upper left corner and they refuse to be dragged to a different spot on my desktop again.

-- edit --
There are 7 icons on the desktop; only 5 have icon files. File permissions and attributes:

`jbland@joe-xlap2-64:~$ ls -l ~/.config/xfce4/desktop/
total 20
-rw-rw-r-- 1 jbland jbland 272 Mar 12 13:18 icons.screen0-1904x1039.rc
-rw-rw-r-- 1 jbland jbland 333 Mar 12 20:47 icons.screen0-3158x1404.rc
-rw-rw-r-- 1 jbland jbland 333 Mar 12 20:57 icons.screen0-3184x1404.rc
-rw-rw-r-- 1 jbland jbland 330 Mar 12 20:47 icons.screen0-3184x758.rc
-rw-rw-r-- 1 jbland jbland 330 Mar 12 16:56 icons.screen0-3184x759.rc
jbland@joe-xlap2-64:~$ lsattr ~/.config/xfce4/desktop/
-------------e-- /home/jbland/.config/xfce4/desktop/icons.screen0-3158x1404.rc
-------------e-- /home/jbland/.config/xfce4/desktop/icons.screen0-3184x759.rc
-------------e-- /home/jbland/.config/xfce4/desktop/icons.screen0-3184x758.rc
-------------e-- /home/jbland/.config/xfce4/desktop/icons.screen0-1904x1039.rc
-------------e-- /home/jbland/.config/xfce4/desktop/icons.screen0-3184x1404.rc`

While getting this information, I see now that I can position an icon as desired and an icon file gets updated. I have no idea why, in this same login session, I can now move icons successfully.

--edit 2--
So, I rebooted, and now I cannot move the icons once again. In addition, the Terminal and two other icons are gone. The attributes of the 5 files are unchanged.