Ok, I have had a play with my version (5) of Outlook Express. The cut off for a text file appears to be 4096 characters which I'd have thought would be adequate.

If you really need a longer signature, the only suggestion I can make is to use the insert text from file option instead.

You can right click on items in your history folder to delete individual items but I would suspet that your history and therefore your autocomplete would soon fill up with unwanted URLs. Would you not be better off adding the URLs you realy want to your favourites?

Jon