When attempting to install the VUEM Agent, the installation process errors out with Error 1001: cannot cast object of type 'System.String' as 'System.String'.
When the VUEM agent installer runs, it modifies the LogOffCheckSysModules key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\WFShell\TWI so the Agent can properly interact with Citrix technology.
In all versions except XenApp 6.0, this key is a REG_SZ value. For XenApp 6.0, this is a REG_MULTI_SZ. To determine which format it should inject new values in, the Agent installer reads the NewProductVersion key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\ in the server registry.
If NewProductVersion is 6.0.0, the installer will attempt to make its modifications as REG_MULTI_SZ; otherwise, for any other version number, it will do so as REG_SZ.
If NewProductVersion is 6.0.0 and for any reason LogOffCheckSysModules has been modified to a REG_SZ (some tools make this change), the installer will not be able to complete the installation process. Likewise, if NewProductVersion has any other value and LogOffCheckSysModules is REG_MULTI_SZ, the installation will fail.
Please make sure that the LogOffCheckSysModules is of the correct type depending on whether the value of NewProductVersion is 6.0.0 (in which case, LogOffCheckSysModules should be REG_MULTI_SZ) or any other value (in which case LogOffCheckSysModules should be REG_SZ).