Microsoft took the stance during its latest Patch Tuesday bulletin that contained fixes for a number of products including Windows XP, which had passed its support cut-off deadline on 8 April.
Announcing the latest set of fixes from the Patch Tuesday release, Dustin Childs, Microsoft Trustworthy Computing group manager of response communications, said that XP was now definitely left to fend for itself.
"For those wondering, Windows XP will not be receiving any security updates today," he said.
"For some time we have been recommending customers move to a modern operating system like Windows 7 or Windows 8.1 to help stay safe."
The comments come after a fix for IE was released out-of-band to patch a major issue that had come to light, and the Patch Tuesday update contains further enhancements to this fix.
"This security update resolves two privately reported vulnerabilities in IE. The vulnerabilities could allow remote code execution if a user views a specially crafted webpage using IE," Microsoft said.
"An attacker who successfully exploited these vulnerabilities could gain the same user rights as the current user. Customers whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights."
Other key fixes cover major products including Office and SharePoint, with two rated as critical and six as important.
The SharePoint fixed was rated as critical, which Microsoft explained could theoretically "allow remote code execution if an authenticated attacker sends specially crafted page content to a target SharePoint server".
The Patch Tuesday update comes after Microsoft extended the deadline for users to install the Windows 8.1 Update release, the benchmark for all future security and software upgrades, as the firm looks to simplify its operating system environments.
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