Microsoft announced its Windows Upgrade Option (WUO) last week. However, organisations and businesses looking to upgrade for free are restricted to 25 Vista PCs.
"If you are a computer administrator ordering on behalf of your company or organisation, you may order a maximum of 25 Windows 7 Upgrade Kits for 25 eligible computers purchased during the eligibility period," HP said in its terms and conditions regarding free upgrades.
"If you need more than 25 upgrade kits, contact Microsoft about a volume licence."
HP was among the first computer manufacturers to announce it would be backing the upgrade scheme.
Dell has similar terms and conditions. In its FAQ on the upgrade program, Dell said: "In addition, the number of Dell Windows 7 Upgrade kits allowed to any one customer is capped at 25 per physical address. Customers with more than 25 PCs are encouraged to pursue Volume Licensing".
Gartner analyst Michael Silver said: "It seems like an artificial thing to do. It just seems silly to force companies to juggle their purchasing plans for PCs".
Silver said it would either force companies to pay twice for an operating system, or prompt them to delay PC purchases until after Windows 7 officially releases.
"Even if you don't deploy Windows 7 on that machine immediately, you want that licence anyway," said Silver.
That also applies to companies that are still running Windows XP by downgrading from Vista on new PCs; they'll want to have the Windows 7 license in hand for later when they do migrate. "If you don't get [Windows 7] for free now, you'll pay later for a licence."
Because of the 25-machine-per-company limit, Silver expects some organisations to defer purchasing PCs until after new machines are available with Windows 7. "That may push PC purchases into the fourth quarter," he said.
"The program's designed so that PCs don't bottom out during the months leading to Windows 7's release."
Two weeks ago, Silver slammed Microsoft's plan to limit XP downgrades from Windows 7 to just six months after its October 22 release. As a result of Silver's comments Microsoft extended the time limit to 18 months.
"Gartner believes that Microsoft designs these program limitations to persuade organisations to enter Enterprise Agreements, enroll licences in Software Assurance or purchase upgrades to obtain rights to run Windows 7," he said.
To avoid paying for Software Assurance, Silver urged companies facing near-term PC purchases to twist some OEM arms.
"Ask your OEM to ignore the limit and give you the free upgrades," he said. Because OEMs administer WUO, they have the ability to do that, and have made exceptions in the past, Silver said.
And if that's not possible? "Delay your purchase," he said.
See all laptop reviews
See also: Microsoft slashes Windows 7 price to £49