I do not understand the question. First, which product (Acrobat/Reader) and its exact version (including minor), which platform/OS version. Second, from which version to which version you upgraded? Third, with which signature other than your own you want to sign? Different signature images for different documents? Acrobat/Reader saves your signature and applies it the next time you sign. You can change your signature but you'll need to do that each time you want to use a different signature. How exactly you change your signature, which is what, I think, you're asking, depends on which product/version you use.