vSphere 6.5 backup/replication jobs hang

vSphere 6.5 backup/replication jobs may hang forever if you’re using Windows Server 2008 R2 (or Windows 7) backup proxies.
 
Agent…Source.log files contain lines similar to the following:

[16.01.2017 16:16:08] <  1380> vdl| Loading VDDK library. Version: 6.5, directory: 'C:\Program Files (x86)\Veeam\Backup Transport\x64\vddk_6_5', 
module: 'C:\Program Files (x86)\Veeam\Backup Transport\x64\vddk_6_5', config file: ''
...
[16.01.2017 16:16:08] <  1380> vdl|   [vddk] VixDiskLib: Initialize transport modes.
...
[16.01.2017 16:16:08] <  1380> dsk|   SSLLoadSharedLibraries: Failed to load OpenSSL libraries. libdir is C:\Program Files (x86)\Veeam\Backup Transport\x64\vddk_6_5
[16.01.2017 16:16:08] <  1380> vdl|   [vddk] PANIC: SSLLoadSharedLibraries: Failed to load OpenSSL libraries. libdir is C:\Program Files (x86)\Veeam\Backup Transport\x64\vddk_6_5
[16.01.2017 16:16:08] <  1380> vdl|   [vddk] Backtrace:
[16.01.2017 16:16:08] <  1380> vdl|   WARN|[vddk] Win32 object usage: GDI 4, USER 3
[16.01.2017 16:16:08] <  1380> vdl|   [vddk] CoreDump_CoreDump: faking exception to get context

OpenSSL DLLs required by VDDK 6.5 fail to load correctly due to a Side-By-Side conflict related to MSVC runtime libraries.

To resolve the issue, download and install Microsoft Visual C++ 2008 Service Pack 1 Redistributable Package on every Windows Server 2008 R2 used by Veeam as a proxy server (including Veeam server itself, if applicable).
 

This is planned to be resolved in a future Veeam Backup & Replication update.