Numerous would-be Windows 7 users are having difficulty installing or upgrading to Microsoft's newest operating system, user reports on a support forum indicated. Other Internet sites, however, showed that most users are happy with the software.

Several users indicated that attempts to upgrade from Windows Vista caused their computers to enter what they described as an endless cycle of reboots.

"My laptop is now in what seems to be a loop of restarting and trying to restore the files," wrote a user named JSchneider21, in a post Friday on Microsoft's Windows 7 support forum. "My laptop meets the minimum requirements for the upgrade," the frustrated customer pointed out.

"This is precisely what is happening to me," wrote another user, Chimaera717. "The [Windows Upgrade] advisor says I am fully compatible, as well," said Chimaera717.

Both users were attempting to install a version of Windows 7 that's offered to students as a download by Microsoft distributor Digital River. A Microsoft spokesperson said the problem typically occurs when such users attempt to download and install a 64-bit version of Windows 7 directly over a 32-bit version of Windows Vista.

Microsoft has said that upgrading from 32-bit Vista to 64-bit Windows 7 requires a so-called clean install. "Microsoft and Digital River are working hard to resolve these challenges for impacted customers," said the spokesperson.

Still other forum members said they encountered similar problems attempting to install Windows 7 off new discs purchased at retail.

User Bryan9, for instance, expressed angst over such a problem. "I have the exact same problem and I bought my new copy from a retail store today. I have spent six hours trying to install this upgrade," reported Bryan9.

It's not uncommon for new versions of software to cause some headaches.

Apple users griped about a range of installations bugs earlier this year when they attempted to upgrade their machines to Mac OS 10.6, also known as Snow Leopard. Many complained that Snow Leopard sent their machines into what's been dubbed "the spinning wheel of death.

Most new software glitches work themselves out over time, either with a fix from the vendor or solutions posted by the user community.

Judging from customer reports on Amazon and other online retail sites, most Windows 7 users have installed the software without a hitch and are pleased with its performance. For instance, the majority of customer reviewers on Amazon had awarded Windows 7 Home Premium Upgrade at least four out of five stars, as of Monday.

Amazon shopper Herbert Freeman said Windows 7 is "everything it promised to be." User Nix Cadavre said the OS is "good enough to switch from Mac to PC."

Microsoft formally released Windows 7 to the public last week. The company's promise to frustrated Vista users was that Windows 7 offers a more streamlined interface, improved compatibility with third-party hardware and software, and lacks Vista's intrusive security measures.

The full version of Windows 7 Professional is $299, with upgrades going for $199. Windows 7 Ultimate is priced at $319, with the upgrade version at $219. The full version of Windows 7 Home Premium is priced at $199, with an upgrade from Vista or XP costing $119.

InformationWeek has published an indepth report on Windows 7. Download the report here (registration required).