http://timestamp.verisign.com/scripts/timstamp.dll not available

Try these servers

http://tsa.starfieldtech.com
http://timestamp.globalsign.com/scripts/timstamp.dll
http://timestamp.comodoca.com/authenticode
http://www.startssl.com/timestamp
http://timestamp.verisign.com/scripts/timstamp.dll
http://timestamp.sectigo.com

With a retry script such as the one included here: Alternative timestamping services for Authenticode

Honestly, I would just try again. But you can use any of the following:

• http://timestamp.globalsign.com/scripts/timstamp.dll,
• http://timestamp.comodoca.com/authenticode, or
• http://www.startssl.com/timestamp.
• http://timestamp.sectigo.com