Doc opens as read only and cannot replace original document when I edit it

I run LibreOffice 5.3 on a Windows 10 laptop.

Almost at random, a document I open will be read only. To enable editing is simple, but once I do I cannot save my document without renaming it!

I save my documents as Word 2007-2013 docs. Could that be why I can’t open them proper?

Please see if this question has an answer for your problem.

Sorry, does not help, I do not use preview pane.

I do save my documents as Word docs. Could that cause my problem?

The problem you describe is not directly related to file format, but is (I’m sure in it) caused by some other process accessing the document and blocking write file access. The preview pane is one feature that may do that, but not the only one. There might be others, like antivirus, or file details in Explorer (which doesn’t show the preview, but still reads document to get its title, author etc.) And the tools might be format-specific, so yes, using ODT might make difference.

Very possible. My document no longer causes trouble, but if it arises again I’ll save different and post what happens.