Upgrading to a brand new OS isn't always the smartest move. In the majority of cases, upgrading to Windows 10 probably won't cause significant problems, but there are some situations where it may be ill-advised.
One potential issue for people considering an upgrade to Windows 10 is application compatibility. Most applications that run on Windows 7 or 8 should work with Windows 10, but there are no guarantees. If an organization discovers that a critical line-of-business application does not work with Windows 10, it would need to hold off on upgrading to Windows 10 until the application vendor has a chance to address the compatibility issues.
Another problem that could stand in the way of upgrading to Windows 10 is hardware compatibility. Generally speaking, a computer that can run Windows 7 or 8 should be able to run Windows 10, but it is impossible for Microsoft to test every hardware configuration. It is conceivable that there are machines running Windows 7 or 8 that cannot run Windows 10 efficiently.
Yet another reason organizations might hold off on upgrading to Windows 10 is that the upgrade isn't free for enterprise environments. Organizations that run the Enterprise edition of Windows must pay for the upgrade. This doesn't mean that the organization shouldn't upgrade, but rather that it should plan for the cost involved.
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