Every time daylight savings time comes around, we end up with daily alerts setup on a document library one hour off schedule.
It seems that SharePoint only takes into account the information provided by NotifyTime column and NotifyTimeUTC column provided in dbo.schedsubscriptions table within the content database, and it doesn't check whether this one corresponds to ST or DST times.
We need a way to update the alert to make it grab the current time settings.
Deleting and recreating the alert works, but would have to be manually done for each alert. You could also write some OM to update alerts, but in our testing, the updatealert command will update all the alerts for a given site collection at once.
1. First install the SharePoint Administration Toolkit on your Central Administration server. You can find the toolkit here:
2. Once the toolkit is installed on your Central Administration server, run the stsadm –o updatealert command using the same URL for both -url and -oldurl.
Syntax for updatealert: http://technet.microsoft.com/en-us/library/cc508847.aspx
STSADM –o updatealert –url http://SharePoint2007/sites/alert –oldurl http://SharePoint2007/sites/alerts
Running the command this way won’t make any changes to the alert url, but the action of updating the alert should cause it to go out and grab the correct time. This command will need to be run for each affected site collection. Every time the time changes (twice a year), you will need to run this command to keep alerts current until we have a fix for it.