SSL certificate authentication error due to mismatch in Veeam client versions

Dear Community,

I’m running Veeam Backup & Replication Community Edition 9.5 and replicating offsite to a Cloud vendor. I upgraded it to Version 12 to get bug & security fixed. Upon reaching version 12 I came to know that the Cloud vendor does not support version 12, they only support 11a.

Now the I have tried to downgrade it to 11a but the Database is locked to Version 12 and is not usable.

I’m looking to rebuild on Version 11a and archiving backups. is this possible? Below are some queries and answers you might want to read. 

What is the exact upgrade and downgrade versions?

                Upgrade (Current) Version: Veeam Backup & Replication 12 (12.0.0.1420 P20230223)

                Downgrade Version: Veeam Backup & Replication 11a (11.0.1.1261 P20230227)

•  What Veaam components are being used?

                Veeam Backup & Replication Community Edition package

•  OS details on which Veaam is installed.

                Microsoft Windows Server 2012 R2 Standard

•  SQL/ Database version details?

                PostGRE SQL 15 / Last database backup was taken in Veeam B&R version 12.

•  What storage is being used?

                Local Storage

                Cloud Storage using the Service Provider option

•  Where is Veaam solution deployed ? on premises or on some cloud?

                Local Storage is on host server.

                Cloud Storage is off-site with Orro Group

•  What exact issue is the client facing when replicating to cloud vendor?

                SSL certificate authentication error due to mismatch in Veeam client versions

•  Is it known if the Cloud vendor is using Veeam Cloud connect feature?

                Yes