Adding Sheet Invalidates Digital Signature
 

Would it work if the workbook containing the code was a template, and the
user simply opened a copy?
Don't know......just a thought.

Regards.

"Simon" wrote in message
...
(see various posts on this subject in this group - all without any fix)

Simply put, any macro in a signed excel project that adds or deletes a
sheet
will invalidate the digital signature causing macros to be disabled next
time
the workbook is loaded. Thsi seems to apply to Office XP and 2003 at
least.

It appears that the digital signature includes not only the VBA code
modules, classes, etc. but also the sheets collection! This is
particularly
annoying as the sheets I'm adding (copy from existing hidden 'template'
sheet) don't contain any code and this bug/feature isn't documented
anywhere
I could find.
Obviously, changing the contents of a sheet is possible without
invalidating
the signature. How is adding a sheet any different? Maybe the hashing
algorithm assumes that each sheet always has a code segment and always
includes it - even though it is empty? Is there some way I can ensure that
my
template sheet is code-free and therefore always excluded from the
hashing?
I've tried a workbook cleaning utility but that didn't help.

Any suggestions (that don't involve COM or add-ins) or even a patch to
Excel
from Microsoft would be very welcome.