Windows fonts not immediately useable in application after installing?

Question

Whenever I install a new font on a Windows 2003 server, I can't use it immediately in my asp.net web application. The application gets the font through the CreateFontIndirect gdi32.dll win api, and then use this font to create a dynamic text image in my asp.net application. It seems like fonts get cached somewhere, because I will just get the default font returned.

The font cache gets updated after a reboot, and then I get the correct font, but obviously I wouldn't like to do a reboot on a production server just for getting a new font to work.

Is there a way to flush the font cache?

Sigman

How do you install the fonts? – Whitethroat

I install them by copying them into the windows\fonts folder. Windows shows the installing prgress bar and they appear correctly in the windows\fonts folder so it seems they are installed correctly. – Sigman

btw they are regular TT fonts that normally work in the application, just not immediately after installing them in windows. – Sigman

Answer 1

By default, when you install a new font, only the current session is notified of the change. So if you're logging into the server in a terminal services session (which seems likely) then the ASP.NET application (which will be running in a different session) will not see the change.

When you reboot, the system automatically scans the font directory and "registers" all of the fonts in there into the current session.

To "manually" register a new font, you will need to call AddFontResource and pass in the path to the font.

To make it slightly easier, you could make it so that your app scans the Fonts folder and calls AddFontResource on each file it finds there in it's Application_Start event. That way, when you install a new font, you can just recycle the site (e.g. edit the web.config file) and it'll re-scan all of the files.

Another option would be to put a directory watch (via FileSystemWatcher) on the Fonts folder and automatically re-scan it.

I guess it just depends how often you'll be installing new fonts...

Whitethroat

So there is no possibility to rescan the fonts from outside the application for that particular session? – Sigman

AddFontResource adds the font to the system for the whole session, so you could run another program in same session as ASP.NET to re-scan the directory and call AddFontResource, but whether there'd be much benefit I'm not so sure. – Whitethroat

Well, Telerik certainly agrees with this post! – Longwise

This also applies to services. To get them to "see" a new font the machine has to be rebooted. Just restarting the service does not help. – Olivine

Answer 2

Restart IIS. that should do the trick. rub iisreset from command line or use IIS manager.

Gynoecium

I can confirm that this doesn't work. Dean's explanation seems to be correct. – Ginter

This worked for my barcode application without a system reboot using System.Drawing.Font to create a graphic out of the barcode font. – Adrienneadrift

this answer could solve your problem, give it a try, it solved mine. – Lynnlynna

IIS restart worked for me, as did recycling the appPool on another server. – Horick

Answer 3

I recycle the application pool that use the fonts and it fixed.

Endstopped

Also make sure the font is installed for all users. The combination of app pool recycle and install for all users did the trick for me. – Mitrewort

Answer 4

When installing fonts on a server, NEVER double click them to install, otherwise it only installs for the current user. Instead you should right click the font file and select "Install for all users". The font will then be available right away for use in your web application.

Overman

This helped as I was missing 2 of the 10 fonts I installed. I had not used "Install for all users" That plus the Recycle Application Pool response above got the fonts to show up properly. – Mitrewort