What are the differences between the one that worked, and the one that doesn't?

>I did try it on my Windows 10 (another computer that I just bought). And it worked.
>But my "working" computer is this one. And I would prefer to make it work on this PC. And this software, SecureLink, worked here just about 2 weeks ago, for a long time.
>
>>Do you have another computer or VM on which you can try to install the software?
>>
>>>I think I tried all items you listed below. But to no avail. If I don't find the solution myself, I am screwed.
>>>Clearly my problem is unique; otherwise, the support company (SecureLink) would find the solution. But since I am just one in a "million", they don't give a shit.
>>>
>>>Thanks.
>>>
>>>>I'd try to get support from the company that makes that software:
>>>>
>>>>- Do they have a support phone number?
>>>>- Do they have a support forum with a community?
>>>>- Do they offer downloadable tools such as "complete" uninstallers or "cleanup" tools? Sometimes a failed or incomplete installation can cause subsequent installation attempts to fail. Running a cleanup tool can get you back to square one
>>>>
>>>>>Hi,
>>>>>
>>>>>This is another message regarding my problem installing Secure Link Connection Manager (SecureLinkCM.EXE)
>>>>>
>>>>>Where and how do I view what stops the installation? I am looking at the Event Viewer but I can't find where (if anywhere) the events of failed installation would be shown?
>>>>>
>>>>>If not in the Event Viewer, how else can I figure out what stops the installation
>>>>>
>>>>>Btw, I tried installation after setting Firewall OFF and bringing down the AV.
>>>>>
>>>>>TIA