Simply put, this is not OK.<p>Microsoft has no idea what your situation is.  They cannot possibly predict what the effect of the upgrade will be, no matter how good a job they think they did with Windows 10.<p>What if you depend on some program to do your job and the &quot;upgrade&quot; messes it up irreversibly?  What if you&#x27;re a student with a project due in two weeks and suddenly you&#x27;re unable to open something after the &quot;upgrade&quot;?  What if you&#x27;re in some kind of managed environment that doesn&#x27;t expect the &quot;upgrade&quot;, that is then utterly confused afterwards (perhaps even trying to downgrade your software again)?  I&#x27;m sure these aren&#x27;t the only scenarios that could see big problems.<p>If they&#x27;re so desperate to make people upgrade, they should at least have had the decency to pull an Apple and ship an entire compatibility-VM with their new OS (like Mac OS X 10.0 did) to minimize the chance of a problem.