Error An Invalid Parameter was passed to a service of function” Horizon and TRUE SSO February 8, 2021February 27, 2021 fabioComulative Update, Horizon, SSO, TRUESSO, Windows10Leave a comment When i try to use TrueSSO and Horizon i find this error: Horizon Windows Desktop or App fails with logon error: ‘an invalid parameter was passed to a service or function’ (79644) (vmware.com) We have install the last windows 10 comulative update Fix it Error An Invalid Parameter was passed to a service of function” Horizon and TRUE SSO