I have a user that has a problem when going to sign a document. After a reboot attemt to sign and when the box pops up to actually sign something it just hangs with the fields all grayed out for about a minute. Subsequent attempts there seems to be no issue only the first time. This behavior started a few weeks ago. I have another user without the problem. Any ideas what could be causing it to take so long the first time? Very frustrating for the user.
Is this Windows or Mac, which OS version? Which Acrobat XI version (including minor)? Does this happen after each reboot (you said that already but, please, confirm? Does this happen if before signing the first time after reboot you open an already signed PDF? Does opening of a signed PDF after a reboot before you try to sign happens in acceptable time or is also slow?