I can't launch Firefox due to "This Application Has Failed To Start Because Usp10.dll Was Not Found" error. What can I do?
In order to fix the issue, I suggest you uninstall (Control Panel > Uninstall a program) the browser and then download and install the latest version available. If it doesn't fix the error, run the Dll-Files Fixer utility. It is developed to solve all .dll related issues.
Just reinstall it again. If you do not have the installer, you can download from http://www.mozilla.com/en-US/products/download.html?product=thunderbird-2.0.0.18&os=win&lang=it . If not work, i don't know %) .