Microsoft's monthly Patch Tuesday, when it issues online updates for its operating systems, has set a new record this month.
The October Security Bulletin fixes 34 vulnerabilities, including two critical patches for Windows 7, which doesn't go on sale till October 22nd.
Other updates include patches for Windows Media and Internet Explorer.
Some of the flaws could have allowed an attacker to control a computer remotely.
The vulnerabilities in Windows 7 were detected by developers in the beta (test) versions which were released in limited numbers earlier this year.
As usual, the patches can be installed through Windows Live Update, and most users should get these automatically.
Otherwise, the updates are available here.Meanwhile, critical updates have also been issued for Adobe Reader and Adobe Acrobat for both Windows and Mac. If left unpatched the vulnerabilities could cause the application to crash, or allow remote control of the user's computer. The updates are available here.