Some users have reported that their editions of Norton Anti-Virus detect the Z3TA 2.1 stand-alone .exe file as a potential Trojan virus (referencing Suspicious.Cloud.5) during installation.

This is a false positive report from Norton. The Z3TA 2.1 microhost is not a harmful file to have installed on your system. For more information about false positives, please visit http://service1.symantec.com/sarc/sarc.nsf/info/html/what.false.positive.html

To install Z3TA 2.1 you can try disabling Norton Anti-virus while you let the Z3TA 2.1 installation run.

This and other false positives can be reported to Symantec directly by filling out the form on their website found at https://submit.symantec.com/false_positive/