Office 2010 – about the 64-bit version

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Office 2010 will have a 64-bit version but don’t get too excited.

Office 2010 comes with 64-bit software as well as the usual 32-bit software.

First a little background for those of us who think that 64-bit is a new type of chocolate cookie “64 bits in every bite!”

Microsoft Office, like the computers that run it, is normally supplied as 32-bit software. You’ll almost certainly be running 32-bit Office software right now.

However personal computing is moving to a 64-bit world. 64-bit computers are faster, programming is less complex and, importantly for Office apps, can access more memory.

A standard 32-bit program can access, at most 4GB of RAM. In practice less than that because most 32-bit versions of Windows (some server versions exempted) are limited to 4GB in total.

64-bit programs can access memory, in theory, into the terabyte range. Windows 7 64-bit edition supports up to 192GB of memory, depending on the edition of Windows.

So 64-bit computers with 64-bit compatible Windows and applications are better than 32-bit options, but as usual, things aren’t that simple.

Windows 64-bit editions can run 32-bit programs like Office 2007 however the hardware drivers need to be specially written for 64-bit operating systems – which is one reason why the move to 64-bit has been relatively slow. Many special add-ins also need to be re-written for the 64-bit world.

Happily these difficulties are being sorted out. Most hardware makers supply 64-bit versions of their Windows drivers and software makers have made adjustments to let their software run on the newer systems even if the software itself isn’t fully 32-bit.

Note: this doesn’t work the other way. 32-bit Windows cannot run 64-bit software.

Here at we’ve been running 64-bit Windows for some time and make good use of the additional memory available to run many 32-bit programs plus virtual machines at the one time.

Admittedly, most people don’t need the benefits of 64-bit memory and power which is just as well given the difficulties.

Benefits of 64-bit Office

The main interest in 64-bit MS Office is from the Excel spreadsheet uber-users. These people and companies have truly massive linked worksheets that take ages to run – having faster computers and more memory with 64-bit Excel means you can make those worksheets even bigger and get results faster.

It is mainly in Excel that the greater memory access of 64-bit software becomes useful. Breaking the 4GB memory limit means the worksheets can get much bigger and run faster.

Greater memory availability makes much less difference in Word and PowerPoint because it’s very rare that documents get so large as to near the 4GB limit. More likely the document or presentation will become too cumbersome and unmanageable before the memory limit is reached.

Project users with really big project files might be hitting 32-bit memory limits but there would not be many in that situation.

Outlook is a different story again. It is a complex database program with the major bottleneck being the reading/saving of data to the PST/OST data file.

To get the most, or anything, out of 64-bit Office ALL the components of MS Office have to be 64-bit compatible. ActiveX controls and DLL’s all have to be re-written for 64-bit

If not, some parts of Office won’t run at all.

As we’ll see, this is a major stumbling block for Office 2010.

In short, a 64-bit version of Office is better, but the compatibility issues can be a major stumbling block.

Office 2003 and 64-bit

Despite what many people, including Microsoft staff, have said – Office 2010 is not the first version of Office to have a 64-bit edition.

Office 2003 had a little known and even less sold separate 64-bit edition available. Not many companies bought it because of the compatibility and cost issues. 64-bit hardware was much more expensive and software compatibility problems were rife.

There was no 64-bit edition of Office 2007.

Office 2010 and 64-bit

Office 2010 will be supplied with both 32-bit and 64-bit software in the one disk install package. There will be no extra charge for 64-bit Office 2010.

It seems that both 32 and 64 bit software will be available for all Office 2010  bundles – Microsoft has given no indication that 64-bit software will only be available in the higher priced bundles.

Only the 32-bit software is installed in the normal installation process – there’s no option to choose between 32 and 64bit software even on a Windows 64-bit platform.

Sounds crazy but Microsoft is being cautious and they are right.

Many add-ins, controls etc, apparently even those supplied by Microsoft, have yet to be converted into 64-bit versions.

As Microsoft puts it “recommending 32-bit Office 2010 as the default installation on both 32-bit and 64-bit Windows mainly due to compatibility with existing 32-bit controls, add-ins, and VBA”

If you’re running SharePoint then 64-bit clients are not for you – at least not yet. Some SharePoint features rely on ActiveX controls that, you guessed it, Microsoft hasn’t made a 64-bit version.

(Users of Windows 64-bit may have already struck similar problems with Internet Explorer. The 64-bit version of IE works fine until it needs an add-in like Flash which is only available as 32-bit. That’s why 64-bit Windows has two menu items ‘Internet Explorer 64-bit” and “Internet Explorer” – the latter is the 32-bit version for add-in compatibility. Office 2010 can’t offer 32 and 64 bit apps at the same time.)

What to do?

Until Microsoft and developers get fully up to speed with a dual 32-bit/64-bit world of Office development – it seems prudent to stick with 32-bit Office on Windows 64-bit. You’ll get performance improvements without the compatibility hassles.

In the meantime it’s not a total loss – 32-bit Office applications can access more memory because the underlying Windows 64-bit system can offer up more useable memory. For example a 64-bit computer with 8GB of RAM can supply up to 4GB to Word or Excel if necessary with room to spare – something that a 32-bit machine can’t do. In addition the 64-bit computer and operating system is probably faster and more stable than a similar 32-bit machine.

In a future article we’ll talk about installing and running Office 2010 64-bit.

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