I was shocked to discover that a .sig I inserted from the Outlook 2000 toolbar contained an old email address that had been discontinued months ago.

I'm not certain what the problem was, but a little investigating revealed a very strange behaviour of Outlook -- though it does kind of make sense.

If anyone can shed more light on what really happened, that would be great.

In the meantime, my own approach was to delete all my .sigs and build brand new ones, possibly obliterating the evidence on the way. Nonetheless, I did discover that Outlook insists on storing its signature files in a subdirectory of "Application Data" (not my favourite system, as it buries things in some decidedly inconvenient places). As far as I can tell, any file placed in this directory appears in the signature list (after selecting More... on the toolbar).

However -- and this is where the danger comes -- Outlook seems to create multiple versions of some signature files, for use with RTF and HTML email (which I wish I could disable for outgoing email). That means, you can end up with three signature files for each .sig.

This is good, in that it's possible to edit these files to change the text sizes to something more in line with your other font settings.

But it's bad because, once Outlook has created the extra copies, it forgets that they arose from a text file. Hence, as I discovered, replacing the text version of a .sig file to change the email address (for example) will NOT change the RTF version of that .sig, leaving you in danger of inadvertently distributing an old email address on the rare occasion you send an RTF email.

As far as I can see, there's two ways around this. Either, never reuse the same name for a new .sig (obviously, this is unnecessarily restrictive). Or, whenever you change your .sig, go to the directory "Application DataMicrosoftSignatures" and delete all .RTF and .HTM files.

I reckon Microsoft needs to put some more thought into this one.