Full Disk Encryption Option missing from client install

Question

Dear Members, 
 We have deployed Sophos Safeguard Enterprise 8.20.0.83 in our environment, we have had no issues deploying the client software to our domain joint machines. The policies are very simple and we have started with fulldisk encryption, which we have managed to deploy to a number of our machines. 
 However, we have come across a machine, an HP Probook 450 G5 notebook running Windows 10 Pro (1803) X64, where the "Full disk encryption" + Bitlocker options are not available during the client install. We have checked the partitions on the disk, partitions are NTFS formatted, disk type is set to basic. We have also run tpm.msc to check for any issues with the TPM module and services within Windows, no issues found. Before we proceed to do a full format & re-installation of Windows on this machine, has anybody come across a similar issue and managed to resolve it ?

Any help will be appreciated. 
 Thank you 
 Carl

Carl Korb · Answer

Dear Community, apologies for not getting back to you on this issue. After much troubleshooting and changing the BIOS from Legacy to Secure Boot, we discovered that the Sophos Central AV was deployed with Sophos Central Drive Encryption package. We uninstalled the Sophos Central client, rebooted the machine, re-installed Sophos Central Endpoint (minus the Central Drive Encryption), rebooted and proceeded to install the SGN client, which now had the Drive encryption option available. 
 
 Hope this will help someone in the future if they come across this issue. 
 
 Regards 
 Carl