Windows Installer installs products in units of components - they are the building blocks of the installation. It installs a component if it believes that the component is not up to date or is missing, which it determines from the component's key path. It stores a list of all the components which are installed, and the locations they are installed to, in the Windows registry. This acts as a reference count to decide when to remove the component on uninstallation.
It is therefore vitally important that the component GUIDs are unique to each individual component, and that the composition of the component is the same for each definition of the same component (as identified by the same GUID). It is also essential that resources (files, registry keys) are not defined by multiple different components, as they can be removed prematurely as Windows Installer detects that one of the components owning that resource has reached a zero reference count and should be removed. For more see Rob's blog entry 'Component Rules 101', a copy of which is in the WiX documentation (WiX.chm) or at http://blogs.msdn.com/robmen/archive/2003/10/18/56497.aspx. -- Mike Dimmick -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of teckJBMsia Sent: 18 April 2007 09:43 To: [email protected] Subject: [WiX-users] What is the use of an application (.exe) GUID ? Hi, Following is quoted from WIX Tutorial. <Component Id='MainExecutable' Guid='YOURGUID-83F1-4F22-985B-FDB3C8ABD471'> <File Id='FoobarEXE' Name='Foobar10.exe' LongName='FoobarAppl10.exe' DiskId='1'Source='FoobarAppl10.exe' Vital='yes'> I wish to know what is the purpose of that Guid. Besides that, can WIX search for that GUID before installing a program to make sure that program has not been installed previously ? ( Note : in my case, the product GUID can be same but not the program ). Cheers ! ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ WiX-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/wix-users
