SharePoint error of the day

Today one of our servers in the farm start failing on some sites with the error below. Appearantly we're the only one, Googling on PreInitServer and '[COMException (0x80004005): Cannot complete this action. ' yields nothing. We're hoping a reboot tonight will resolve something here as we recently installed report server in the farm.

Server Error in '/' Application.
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Cannot complete this action.

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Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Runtime.InteropServices.COMException: Cannot complete this action.

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Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[COMException (0x80004005): Cannot complete this action.

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Microsoft.SharePoint.Library.SPRequestInternalClass.PreInitServer(String bstrAbsoluteRequestUrl, String bstrServerRelativeUrl, Int32 lZone, Guid gApplicationId, Guid gSiteId, Guid gDatabaseId, String bstrDatabaseServer, String bstrDatabaseName, String bstrDatabaseUsername, String bstrDatabasePassword, Boolean fHostHeaderIsSiteName) +0
Microsoft.SharePoint.Library.SPRequest.PreInitServer(String bstrAbsoluteRequestUrl, String bstrServerRelativeUrl, Int32 lZone, Guid gApplicationId, Guid gSiteId, Guid gDatabaseId, String bstrDatabaseServer, String bstrDatabaseName, String bstrDatabaseUsername, String bstrDatabasePassword, Boolean fHostHeaderIsSiteName) +359

[SPException: Cannot complete this action.

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Microsoft.SharePoint.Library.SPRequest.PreInitServer(String bstrAbsoluteRequestUrl, String bstrServerRelativeUrl, Int32 lZone, Guid gApplicationId, Guid gSiteId, Guid gDatabaseId, String bstrDatabaseServer, String bstrDatabaseName, String bstrDatabaseUsername, String bstrDatabasePassword, Boolean fHostHeaderIsSiteName) +479
Microsoft.SharePoint.SPSite.PreinitializeServer(SPRequest request) +666
Microsoft.SharePoint.SPWeb.InitializeSPRequest() +548
Microsoft.SharePoint.SPWeb.EnsureSPRequest() +75
Microsoft.SharePoint.SPWeb.get_Request() +74
Microsoft.SharePoint.WebControls.SPControl.SPWebEnsureSPControl(HttpContext context) +613
Microsoft.SharePoint.WebControls.SPControl.GetContextWeb(HttpContext context) +41
Microsoft.SharePoint.ApplicationRuntime.SPRequestModule.PostResolveRequestCacheHandler(Object oSender, EventArgs ea) +595
System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +80
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +171