Have you applied Paragraph and Character Styles to your text?
Have you embedded the fonts (generally not recommended)?
Do you have the font licences to create ePubs with these fonts?
Which application(s) are you viewing the ePub in (e.g. iBooks)?
What does the ePub validator state: EPUB Validator (beta) ?
Just a few ideas!
Here's what I did:
Have you applied Paragraph and Character Styles to your text? YES, I DID.
Have you embedded the fonts (generally not recommended)? I WANT TO EXPORT A FLO EPUB. CANT FIND THE OPTION WHERE IT ASKS FOR EMBEDDING FONTS
Do you have the font licences to create ePubs with these fonts? TRIED TO FIND OUT HOW (I WORK ON A WINDOWS SYSTEM) I CAN EASILY SEE WHICH FONTS HAVE WHAT LICENSES. COULD NOT FIGURE THAT OUT SO FAR.
Which application(s) are you viewing the ePub in (e.g. iBooks)? ADOBE DE (VERSION 4.0.3)
What does the ePub validator state: EPUB Validator (beta) ? NOT TRIED OUT THAT ONE YET,
Just a few ideas!
When you export to Reflowable ePub there's a dialogue box called "EPUB - Reflowable Layout Export Options", in the CSS tab there's an option to tick/untick Include Embeddable Fonts.
Try with some different fonts and see what happens.
Try the ePub on a device, app or maybe Readium
Problem is I work with a FLO fixed layout epuc. The the option is not presented.
The strange thing was that some other fonts worked, but e.g. the Open Sans ( a google open font) was not working.
What I discovered deep down in the properties of the font files in the Windows font folder that is has a tab 'Details' and that tab has property list and one is called "possibility to embed .. '. Some fonts say that the font can be "adjusted" or something in Dutch is called "bewerkbaar". Other fonts have a property label here that says 'limited' or 'installable". What is seriously miss is an overview of what fonts have what properties! This is ridiculiously hidden.
Funny thing also is my file passes the InDesign FLO export option without any mentions of font problems or license characteristics.
Last thing: we indeed also just discovered that opening our epub on a different device solved also some problems.
It seems Adobe Digital Editions (which is the standard epub viewer ont my machine) has some serious flaws when used on a (only?) a WIndows platform.
Sometimes a file just not want to open and on moste occassions this also gave font problems: some fonts that are perfect in the InDesign file were missing in the epub (in our case a font called AmerType) When I transported the exactly same file and opened it with iBooks it looked perfect. Search me, if you ask me why, but Adobe DE will be deleted asap as standard epub viewer. It was the cause of a lot of faulty diagnoses :-(
Oh – you mean a Fixed Layout ePub, That's shorted to FXL, not FLO!
Yes, ADE does seem to have some issues. Try it on a device such as a Kobo.
I tested Open Sans version 1.10 and it seems to work fine with ADE 4.0.3.
Deleted ADE and installled Radium. Now the epub looks as it's supposed to do.
I fail to understand why ADE has this problems, but maybe it's only on a windows platform?
I also Always opened epubs super slow.... Strange that Adobe has all the nice design programs but their ebook readers is problematic.
Anyway thanks for all you tips! I can move on again now. Problem solved.
Glad you got it sorted though I wouldn't rely on Radium. You want to test the ePub on all the actual devices you want it to be used on.