To switch back to the Bitvise SSH library in EFT version 8.0 to 8.0.5 you need to go to the advanced properties file, by default this is found in:

 C:\ProgramData\Globalscape\EFT Server

You will then need to open this in a notepad and add the following line (it is a good idea to take a copy of this file before making this change):

{
"UseLegacySFTP":true
}

Make sure this is then saved and then restart the eft services. This change will have taken effect. 

In version 7.4.11 you will need to make a new registry key in the following location: 

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\GlobalSCAPE Inc.\EFT Server 7.4\

With the following options:

ype: DWORD

Value name: UseLegacySFTP

Value: true = use legacy SFTP; false or doesn't exist = use updated SFTP

Restart Required: yes

Backup/Restore: yes

Once this is done you will need to restart the EFT services and the change is complete.