is there any way to backup WSS3.0 (embeded sql 2005 express)so that it can restore to the point of failure, or at least restore to 15minutes before the failure, such as sql server transaction log backup?

Put the system on a VM and do snapshots every 15 mins. At the worst you will have a snapshot available 15 minutes before the failure.SP 2010 "FAQ" (mainly useful links): http://wssv4faq.mindsharp.com/default.aspx WSS3/MOSS FAQ (FAQ and Links) http://wssv3faq.mindsharp.com/default.aspx Both also have links to extensive book lists and to (free) on-line chapters

Mike's got a good idea, but please keep in mind that's only supported in a single server environment: blogs.msdn.com/b/uksharepoint/archive/2009/02/26/virtualizing-sharepoint-series-introduction.aspx If you've got multiple servers, the only way you'd be able to get that kind of coverage is to use SQL Server backups and plan on restoring your content databases or to run very frequent backups through Central Admin or STSADM which can be one heck of a performance hit on your SharePoint server, or to use an additional tool such as Microsoft's Data Protection Manager 2007 or something from vendors like AvePoint, Quest, Idera, etc for that kind of coverage. JohnMCTS: WSS v3, MOSS 2007, and SCOM 2007 MCITP: Enterprise Project Management with Project Server 2007 Now Available on Amazon - The SharePoint 2010 Disaster Recovery Guide. Also available - The SharePoint 2007 Disaster Recovery Guide. My blog: My Central Admin.

<grinning> > please keep in mind that's only supported in a single server environment Ah, but John, he's running WSS 3.0 with embedded SQL Server 2005 Express, so he *must* have a single server environment. Greetings, Mike SP 2010 "FAQ" (mainly useful links): http://wssv4faq.mindsharp.com/default.aspx WSS3/MOSS FAQ (FAQ and Links) http://wssv3faq.mindsharp.com/default.aspx Both also have links to extensive book lists and to (free) on-line chapters

<grinning> > please keep in mind that's only supported in a single server environment Ah, but John, he's running WSS 3.0 with embedded SQL Server 2005 Express, so he *must* have a single server environment. Greetings, Mike Note: The correct term for the version of SQL Server 2005 Express that is embedded in a Basic installation (or Advanced+single-server installation) of WSS 3.0 is "Windows Internal Database". If that term had been used here, there would be no conflicting opinions here about whether the Original Poster is using a single server or not! In any case, John's info is useful for when multiple servers are in use. SP 2010 "FAQ" (mainly useful links): http://wssv4faq.mindsharp.com/default.aspx WSS3/MOSS FAQ (FAQ and Links) http://wssv3faq.mindsharp.com/default.aspx Both also have links to extensive book lists and to (free) on-line chapters

thank you both, yes I am on a single server. but VM snapshot is not good since it causes problems in many cases, fills storage space, also not working well with VDR, also when LUN crashed, the snapshot lost too. My plan is to backup differentially every 15 mins to a different LUN just like to backup the sql tlog. the worst case is losing 15minutes data. I guess I have to use John's suggestion to backup every 15 minutes differentially, not sure if this will work out, or there is better suggestions for a single server backup.