Install application error

There's a huge difference between "I started setup while being logged on as administrator" and "I right clicked setup and selected 'run as administrator'" - do the latter, please.

That is what I did. ie. right-click exe, selected 'run as administrator'.

Are you able to verify that indeed you cannot write to syswow64 (try it in explorer)?
If you can do it in explorer, retry the installation, but this time, monitor it with procmon.exe https://docs.microsoft.com/en-us/sysinternals/downloads/procmon and filter for the result "access denied" and see if procmon can confirm it.

The properties tab shows that no group or user name has write access to syswow64.
Trusted Installers has only list folder contents ticked but the edit option does not enable the options to change read, write etc.


I am in the process of moving all my applications from a Windows 7 PC to Windows 10 and have installed a number of other applications without a problem.

Ok, on an elevated command prompt (rightclick cmd, select to run as administrator), launch:
icacls c:\windows\SysWOW64
and share the output.

Should be

SysWOW64 NT SERVICE\TrustedInstaller:(F)
         NT SERVICE\TrustedInstaller:(CI)(IO)(F)
         NT AUTHORITY\SYSTEM:(M)
         NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F)
         BUILTIN\Administrators:(M)
         BUILTIN\Administrators:(OI)(CI)(IO)(F)
         BUILTIN\Users:(RX)
         BUILTIN\Users:(OI)(CI)(IO)(GR,GE)
         CREATOR OWNER:(OI)(CI)(IO)(F)
         APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(RX)
         APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE)
         APPLICATION PACKAGE AUTHORITY\ALL RESTRICTED APPLICATION PACKAGES:(RX)
         APPLICATION PACKAGE AUTHORITY\ALL RESTRICTED APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE)

Select allOpen in new window

You might have to switch off Defender for installing - shouldn't be needed, but Defender might think the installer is malicious.

re. icacls c:\windows\SysWOW64
c:\windows\SysWOW64 NT SERVICE\TrustedInstaller:(F)
                    NT SERVICE\TrustedInstaller:(CI)(IO)(F)
                    NT AUTHORITY\SYSTEM:(M)
                    NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(F)
                    BUILTIN\Administrators:(M)
                    BUILTIN\Administrators:(OI)(CI)(IO)(F)
                    BUILTIN\Users:(RX)
                    BUILTIN\Users:(OI)(CI)(IO)(GR,GE)
                    CREATOR OWNER:(OI)(CI)(IO)(F)
                    APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(RX)
                    APPLICATION PACKAGE AUTHORITY\ALL APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE)
                    APPLICATION PACKAGE AUTHORITY\ALL RESTRICTED APPLICATION PACKAGES:(RX)
                    APPLICATION PACKAGE AUTHORITY\ALL RESTRICTED APPLICATION PACKAGES:(OI)(CI)(IO)(GR,GE)
Successfully processed 1 files; Failed processing 0 files

Windows Defender is not in use I have Bitdefender Anti-Virus

Then switch off that AV while installing.

Let's not skip procmon.

Do as suggested before and use procmon to verify if there really are access denials.

What is procom

It is linked in my comment. Again: https://docs.microsoft.com/en-us/sysinternals/downloads/procmon
It is a monitoring software that shows what happens behind the scenes.

Thanks for your advice but following a reboot the install ran without a problem.

Ok, great. Now please close the question by selecting your own solution as answer.