Check your antivirus or Windows Defender Firewall. Ensure that network traffic on ports 1861 (TWAIN) , 137-139 (SMB) , and 445 (SMB) is allowed.
Configure SMTP settings on the eStudio 256 (Admin > Network > SMTP Client). Use a Gmail or Office 365 SMTP relay (App password required). Then users scan directly to their email inbox. This bypasses drivers completely. toshiba estudio 256 scanner driver work