I have documents in Calibri 8. Every time I save it and open it the next day, it's all in Calibri 11. And the double spaces between sentences have been removed. Why is this? How do I stop it?

Check to see if your document is set to update styles from the template upon opening.

1. Developer Tab
2. Document Template button
3. The checkbox for updating styles should be unchecked.

It was already unchecked. But now when I test again, I find it seemed to be doing it if I open documents saved in a previous version of Word. Looks like it's not compatible with itself.

"saved in a previous version of Word." ??
What is the File Type/Extension?

docx, I only mean one version older. Maybe something changed with the fonts on my computer. I have put Windows 11 on recently on top of Windows 10.

Verify that the default font is correctly specified. In the Font dialog box (Ctrl+D), choose the font you want as the default and click the Set as Default button. You can choose the option to change the current document, only. This should prevent the font from changing during typing.

__________________
Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional

I assume my default is Calibri as a blank document types in that (although that dialog only allows me to change the default, not see what it already is!) Is Calibri a rare font I didn't have before? I have a vague memory of selecting one of the few fonts which is variable spacing and also distinguishes between the number one, both cases of the letter eye, and both cases of the letter ell. It's amazing 95% of fonts have a few of those precisely the same! IiLl1 - they are all different in my browser, what do they look like to you?

Calibri has been available for a while. I think Win7.
However, I bet that update to Win11 is your source of problems. Try a Repair of your Office installation or go straight to Uninstall/Reinstall.

Calibri was first supplied with Windows Vista and has been included in every release since then.

Reinstalling Office is unlikely to resolve anything if the font file is damaged or if, for example, the document template has a macro that reformats the document or modifies the Style using Calibri 8. After all, it's not just the font that is being altered - the line spacing, too, is affected.

It's also possible the document has acquired some of corruption. Corrupt documents can often be 'repaired' by inserting a new, empty, paragraph at the very end, copying everything except that new paragraph to a new document based on the same template (headers & footers may need to be copied separately), closing the old document and saving the new one over it.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

This is not a system setting but is set in each document. (referring to the setting to update styles from template)

Yes, could be Windows 11. It's documents from before the Windows upgrade that have the problem. But once I change the font size and the spacing, it remains correct.

It's not the documents that are corrupt, they appear fine otherwise, and there are about 70 of them.

I guess the OS changed some minor things in fonts I seem to have stumbled on.

Well, that's not what you originally said:

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

It only seems to happen once per document, but I was dealing with a lot of documents so I was mistaken. So how did some idiot programmer manage to screw this up?

To err is human, but to really (!) things up requires a programmer.

The problem likely has nothing to do with any programmer screwing this up. It may all be put down to a hardware-related fault that impacted your Windows upgrade - or even a printer driver that also needs updating.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

If a printer driver can mess up my word document, that is a monumental programmer screwup. I've never printed any of those documents. All it did was forget the font size, and that I like two spaces between sentences. How did it even manage to delete those spaces? That wasn't a preference I set, I had manually pressed the space bar twice after each fullstop. And it deleted them! In fact your forum is doing the same! Is there a new religion against double spacing? It's my personal preference, please leave it alone.