Err.Number=-2147023570

When I run a dts package using a package scheduler, I get following error number: Err.Number=-2147023570. The error happens after following snippet of code(after CopyFile function) :
Set objFSO = CreateObject("Scripting.FileSystemObject")
sSource = DTSGlobalVariables("sSource").Value & sDate & "VEH.TXT"
sDest = DTSGlobalVariables("sDest").Value & sDate & "VEH.TXT"

Err.Clear
objFSO.CopyFile sSource, sDest, True


When I execute package manually, I do not get an error. I only get the error when it is run from the scheduler.

Appreciate any help.

Dhiresh