Backup Exec console crashes after installing .NET Framework 4.8.

Problem

After installing .NET Framework 4.8 on the Backup Exec media server , the Backup Exec console crashes when starting, as shown in Figure 1. 

This issue is also observed on servers or workstations with the Backup Exec Remote Administration console installed.

Figure 1

Error Message

The following error is seen in the Windows Application Event log:

Faulting application name: BackupExec.exe, version: 20.0.1188.1863, time stamp: 0x5bc0c010
Faulting module name: KERNELBASE.dll, version: 6.3.9600.19269, time stamp: 0x5c5e079f
Exception code: 0xe0434352
Fault offset: 0x0000000000008e6c
Faulting process id: 0x1554
Faulting application start time: 0x01d4fb20fc5c3b3d
Faulting application path: C:\Program Files\Veritas\Backup Exec\BackupExec.exe
Faulting module path: C:\Windows\system32\KERNELBASE.dll
Report Id: 3a3f9d26-6714-11e9-80ee-005056053431
Faulting package full name:
Faulting package-relative application ID:

Application: BackupExec.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.Reflection.AmbiguousMatchException
   at System.RuntimeType.GetMethodImpl(System.String, System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])
   at System.Type.GetMethod(System.String, System.Reflection.BindingFlags)
   at BackupExec.ThemeManager..cctor()

Exception Info: System.TypeInitializationException
   at BackupExec.ThemeManager.ChangeTheme(System.String, System.String)
   at BackupExec.App..ctor()
   at BackupExec.App.Main()

Cause

.NET Framework 4.8

Solution

Backup Exec 20.x : This issue has been addressed in Backup Exec 20.5 and above, which is now available in the Download Center.

Backup Exec 16 FP2:  This issue has been addressed in Backup Exec 16 FP2 Hotfix 506023  which is now available in the Download Center.

Backup Exec 15 and older versions : Please upgrade Backup Exec to latest version 20.5 and above or follow the below mentioned workaround.

Important:

It is recommended to upgrade to the latest available version of Backup Exec. Upgrades can be found in the Downloads Center.

Click here for latest Backup Exec Version

Temporary workaround Solution:

1. Uninstall .NET Framework 4.8 and reboot server. This update will be listed as KB4486105 (Windows 2012 R2), KB4486081 (Windows 2012), KB4486129 (Windows 2016), KB4486153 (Windows 2019) in the list of installed updates.

2. For Windows 2008 R2, remove .NET Framework 4.8 through Programs and Features in Control Panel.

Note: In case of Windows 2008 R2, re-install .NET Framework 4.x from Backup Exec install media (\Veritas\BE\WinNT\Install\DotNetFx ) after uninstalling .NET Framework 4.8.