Those fonts probably aren’t missing.
Error dialog windows can be really frustrating. They pop up and demand your attention, when you just want to get to work on something. Sibelius 7 has thrown this missing font error for me a few times:
Most likely the fonts aren’t missing, but simply disabled, which makes the fix really easy. Here’s how to re-enable the “missing” fonts.
First, open the application Font Book. This native OS X font manager should be located in your Mac’s Applications folder.
Second, search for the missing fonts. Font Book has a search field in the upright corner. Type in the names of the missing fonts.
Enabled fonts are shown in black text. Disabled fonts are grayed out and are labeled “Off” on the right hand side.
Third, enable the fonts. Select the fonts you want to re-enable. Then hit Shift-Command-D. You can also enable fonts by using the menu bar by selecting Edit > Enable Fonts. The fonts should turn black and the “Off” label will disappear.
Lastly, close Font Book and reopen Sibelius. If you enabled all the “missing” fonts, you should be good to go. The error shouldn’t pop up this time, however, it may happen again in the future.
Why does this error occur?
I’ve had to run the fix a couple times now. I don’t know why this error seems to reoccur. If you know why those Reprise fonts sometimes disable themselves, please send me an email or comment below.
Being a graphic artist as well, I know that fonts are notorious for becoming corrupt, conflicting with other fonts, and generally being a hassle to manage. You might think being a musician is a good way to get away from graphic design problems, but unfortunately software like Sibelius relies on fonts to display notation. At least the fix for this error is easy to do and only takes a minute.
The fix I posted above seemed to only work for a while. Occasionally, I would have to run the fix again, which is to say, it wasn’t much of a fix. So, I dug in further and found a real, permanent fix.
The issue was with duplicate fonts. The strange bit was that it wasn’t duplicates of the Reprise family, which was the family of fonts that Sibelius said were missing. Instead it was duplicates of various other fonts that Sibelius uses.
By referencing this forum post and this forum post, I figured out which fonts Sibelius requires and, thus, which ones might be causing problems. Then, for clarity’s sake, in the Font Book application I created a new Collection (File > New Collection or ⌘N). After that I did a search for duplicate fonts (Edit > Look for Enabled Duplicates… or ⌘L) and looked in the Sibelius font collection for any that were flagged. Sure enough, about a third of the fonts that Sibelius uses had duplicate copies. One by one, I “resolved” (deleted) the duplicate fonts, then rebooted. Problem solved.