All my documents have changed to 'CDYUUQG' files, and contain gibberish

Windows Defender found something bad on my pc and got rid of it.

After restarting my pc, all of my libreoffice documents had changed to “ODT.CDYUUQG” files, and are now either unopenable, or contain only a line or two of gibberish, like: “µ*›Ò¯¹�ÏiÖ[-ã�ù¿m¤D Þ¼]”. I mean, that’s now the whole of the document!

What on earth happened and how can I [easily!] fix it / restore my documents to their ‘normal state’ ? (Please explain step by step like you’re talking to a four year old!)

This looks like a malfunction of your Windows Defender. Did you already search MS related forums for the problem? What size is the renamed document (as shown in your file manager)? Did you try to simply cut the added extension (including the dot) and subsequently open the file? What version of Windows are you running? (Version of LibO?)

If you add some relevant information it should be more likely you get help. Would you mind attaching one of the files?

[This is not an answer, but I see no other way to continue this thread without writing in this space. Like so much of libreoffice, this is a muddle.]

Thank you for your response.

Malfunction of Windows Defender? Not a clue, and no, I hadn’t searched any Microsoft forums yet, hoping it would be a simple fix and hoping to avoid a many hours long search for futility, as so many computer ‘help’ forums are. I also wrote here since the only items on my pc affected were every single libreoffice document.

What size is the renamed document? I don’t know to what you are referring, since, as I said in my original question, all of my libreoffice documents on my computer suddenly changed to this strange “ODT.CDYUUQG” suffix after the original files’ names. The documents range from very small to moderately large. Most are simple text documents of a few pages or less.

Since reading your suggestion I have attempted to “cut the added extension (including the dot)”, but simply renaming the file(s) does nothing, as they remain the mysterious “CDYUUQG” type of files.

I am running Windows 8, with LibreOffice 4.3.5.2.

If you google “CDYUUQG” they will, among billions of resources, find exactly one match: this thread. This seems to be a rather specific problem with your system. Everything we can do is guessing, or (as @dajare does) hope, you have activated backups, and they ere not corrupted. If a tank rolled over your Chevy and left it 1 ft high, you blamed Chevrolet? Yes, of course. The Ford cars in the same road were not damaged.

Can you create a new Writer Document, save it and open it and see the plain text? Does it save it as .odt file?

You could try looking in the backup folder in your user settings directory. On Windows 8 it should be found at:

 %appdata%\Roaming\LibreOffice\4\user\backup

(See the full information on location of these files in the LibO Wiki.) It might be that you can restore at least some of your files from that location.