Hello to everybody!

I'm using Xubuntu 12.04, XFCE 4.10, and Thunar 1.4.0.

Some weeks ago, i used this guide to replace Thunar with SpaceFM (changing wherever it said PCManFM for SpaceFM)

I've reverted it, uninstalled SpaceFM and everything went good. I installed LibreOffice as I need some options that Abiword and Gnumeric didn't give me. When clicking an ODT file, Abiword was opened, so I then uninstalled Abiword and Gnumeric.

When I try to open some .ODT, .XLS or .txt files on my desktop, i get the error

"File can't be opened
Failed to execute program /usr/bin/Thunar: Success"

But when I open those same files from my desktop folder, using Thunar, I can open them normally. Also, I can open the trashcan from my desktop without any problem.

I can, for example, "right click>open with LibreOffice Writer", but I'd love to get the double clicking working again. How can I solve this problem?
Thanks in advance!