Microsoft is preparing to release a new version of a software patch after the first version caused problems on some systems.

The software giant disclosed last week that users of certain HP products and Sunbelt's Kerio Personal Firewall experienced problems after installing updates issued as part of its April patch release.

Microsoft later added that certain nVidia drivers were also affected.

The problems included blocked access to special folders like My Documents and My Pictures, and Office applications that stopped responding when users tried to save files in My Documents. In some cases Internet Explorer became unresponsive.

Microsoft has published instructions on how to fix the issues. But users unable to make the adjustments will be able to access the updated patch on 25 April. The update is only required for users who have experienced problems.

The patch will be automatically distributed through Windows Update, Microsoft Update and Automatic Update services.