From Mozilla

May 31, 2010 08:08 GMT  ·  By

The first official taste of a 64-bit (x64) flavor of Firefox 4.0 for Windows is now available for download from Mozilla’s FTP servers. At the end of the past week, Mozilla was hard at work wrapping up the first 64-bit Builds of the next generation of its open source browser. At this point in time, early adopters can grab a very early preview release of the next major iteration of x64 Firefox. Obviously, the download is designed for testing purposes and not for deployment into production environments. And there’s also a small trick to get it to work on your computer, especially if you aren’t accustomed to testing pre-release software.

At the end of the past week, I was telling you to get ready for the first 64-bit (x64) Firefox downloads for Windows 7. What testers are now able to try out is an Alpha preview Build of x64 Firefox 4.0, which can be installed on various Windows versions, including Windows 7. It is important to note that this is a pre-Alpha release, and not even the fully fledged Alpha development milestone.

In fact, Mozilla is offering for download Firefox-3.7a5pre.en-US.win64-x86_64. And don’t be tricked about the Firefox 3.7 reference, remember v3.7 is no more, Out of Process Plugins (OOPP) will be delivered tomorrow in Firefox 3.6.4, and the rest of 3.7 was folded into 4.0. There are a few downloads for Windows users, the most important of which is a .ZIP archive that contains the browser, or the installer, designed to streamline deployment. While the actual installation of 64-bit Firefox 4.0 pre-Alpha will pose no problems, running the browser is a different matter altogether.

Some testers have indicated that, following installation, on the first run of x64 Firefox, they received an error informing that MSVCR100.dll was missing. As a direct result, 64-bit Firefox 4.0 pre-Alpha did not start. This is valid for both the installer and the .ZIP. In fact, this is a simple packaging issue, but the best thing about it is that it is extremely easy to resolve.

Essentially, in order to run the pre-Alpha Build of 64-bit (x64) Firefox 4.0 on Windows 7, users will need Microsoft Visual C++ 2010 Redistributable Package (x64). According to Microsoft, “The Microsoft Visual C++ 2010 Redistributable Package installs runtime components of Visual C++ Libraries required to run applications developed with Visual C++ on a computer that does not have Visual C++ 2010 installed.” So just make sure to have the Visual C++ 2010 Redistributable Package (x64) installed, in order to be able to run the Alpha preview of 64-bit (x64) Firefox 4.0 for Windows 7.

The Alpha preview of 64-bit (x64) Firefox 4.0 for Windows 7 (Firefox-3.7a5pre.en-US.win64-x86_64) is available for download here.

Microsoft Visual C++ 2010 Redistributable Package (x64) is available for download here.

Firefox 3.7 Alpha 4 / Mozilla Developer Preview of Gecko 1.9.3 Alpha 4 for Windows is available here.
Firefox 3.7 Alpha 4 / Mozilla Developer Preview of Gecko 1.9.3 Alpha 4 for Mac OS X is available here.
Firefox 3.7 Alpha 4 / Mozilla Developer Preview of Gecko 1.9.3 Alpha 4 for Linux is available here.

Firefox 3.6.3 for Windows is available for download here.
Firefox 3.6.3 for Mac OS X is available for download here.
Firefox 3.6.3 for Linux is available for download here.

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