Terrible font rendering in some applications but not others

Let's try to build an answer with the full information here...

This is a known issue with Microsoft Update KB3013455, released on the 10th February 2015.

For a quick way to check if you have the update installed, open a DOS command prompt and type:

wmic qfe list brief /format:texttablewsys | find "KB3013455"

If this returns no text at all, the update is not installed; if it is installed, you'll see KB3013455 and more text printed out.

The issue can be resolved by either

1. uninstalling the update (but this will leave you with a security vulnerability). A reboot will be required.

2. Installing a subsequent update (the Microsoft official fix, released on the 18th Feb 2015):

   To resolve this issue, install update 3037639. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

   3037639 Fix for text quality degradation after security update 3013455 (MS15-010) is installed.

   This fix will take you to a page where it seems you're downloading the original KB3013455 all over again. Keep going, when you actually click to download you will get an option to get the fix, KB3037639.

   A reboot will be required.

   The fix was later included in Microsoft's automatic updates in March 2015.

Edit the list below to add affected systems:

• Windows Vista SP2
• Windows Server 2003 SP2
• Windows Server 2008 SP2
• Windows XP (for people on the Custom Support Program that keep receiving patches for XP)
• Windows FLP
• Windows Embedded (WEPOS, POS Ready 2009)

Edit the list below to add affected Fonts (only some font sizes show problems):

• Arial
• Courier New
• Times New Roman
• many others

Description of the problem (from here):

Essentially the small fonts (8-20pt) that normally result in a one-pixel line (think of lowercase "b" or "t" or "d") would now be a random mess between 1 and 2 pixels. Turning on "Clear Type" or font smoothing does "smooth" the garbage and it doesn't look as awful but that doesn't make the text any more readable.

Check the following link to fix it:

https://productforums.google.com/forum/#!topic/gmail/U10waTf6ogI

Author: vince31
go to start --> control panel --> security --> view installed updates search for or find KB3013455 installed on 2/11/15 highlight it, right click and select uninstall.

Your PC will need to restart and windows will configure the changes but all should be back to normal after that

You can try this in Firefox and see if it helps...

Inside about:config, the gfx.font_rendering.cleartype_params.rendering_mode definitely changes the way the fonts are rendered on Firefox under Windows OS. You can make the changes and see live what the differences are. What you are going to want to do is actually search for this value and make sure it is the only one visible in your about:config window. The reason for this is below.

---

The options are as follows:

• -1 (Firefox default) screenshot
• 0 (default) screenshot
• 1 (aliased) screenshot
• 2 (GDI Classic) screenshot
• 3 (GDI Natural) screenshot
• 4 (Natural) screenshot
• 5 (Natural Symmetric) screenshot

A word of caution. When making changes to this value on my system, choosing 1 completely removes all text rendered in the browser. This means all your tabs, interface, webpage and about:config text might become completely invisible. If this happens, don't freak out, just double click on the bar where the value should be and change it back to 0 or -1. This is why you want to do a search for the actual value first, so that there is only one entry visible and you can change it back if something goes wrong. Trust me, I learned the hard way.

Source: BugZilla