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manoj_sheth
06-13-2008, 07:16 AM
Hi,

We have a problem signing and distributing our Excel files with Macros in it.

The problem is this,

(1) We have many Excel files that refer to the same heavy code. So we created libraries (XLA) of the common functions.

(2) We sign both XLA to our users and ask them to put in their default Add-Ins location (c:\documents and settings\<user>\Microsoft\Addins. They are also asked to check them in their Tools->Addins menu

(3) The Excel files are accessed over the web-server (embedded in IE).

(4) We sign the Excel files in a non-expiring [timestamped] way so that even if certicate expires - the signature is valid. The Excel Workbooks reference the XLA files in their VBA project. When the developer signs it, the XLA files are in c:\Documents and Settings\<developer>\Microsoft\Addins

(4) The problem we are facing is that whenever Excel is opened by the user, it replaces the developer Excel with the known reference (in the user's own folder). But the moment it does that, the signature is invalid. Therefore Excel does not play the macro (the security being high).

For some technical reason, it is not possible to force a common location for the developer and all the users. Is their any other way to ensure that users are able to use the macro functionality without lowering their security?

mikerickson
06-13-2008, 09:17 PM
You could set it up so that the user ran an install macro instead of just putting the file somewhere. That would give you some control over where the XLA file was put. The Install code could store the file path to the XLA file somewhere in the user's copy of Excel.

Bob Phillips
06-14-2008, 04:08 AM
Get a proper installer and use self-extacring installers to install them.