Hi @Bill_Wang ,
We can not give more suggestions to this because it would require us spending time on your system/setup to understand what's happening, and even in that case it might be a totally unknown issue requiring hours of work.
Certificate-based problems are fairly common, and you'll struggle a bit to understand the concepts, but once you do it will all make sense. I suggest reading some tutorials to understand how a certificate works.
However, you might also hit infrastructure problems, like some firewall that blocks communication (and that firewall might not be always under your control, making in turn a nasty experience).
Whenever I see issues like this, I try to take out of equation the infrastructure elements that are in-between. For example, I'd try to install Kepware in a VM in the same AWS cloud region and see if that works fine, or if Kepware works from your own computer. Basically everything to eliminate what could trigger the issues you see.
If your company has an active subscription to ThingWorx and/or Kepware, you can always open a Tech Support case - I saw you did that, what's the outcome from that case?
Unfortunately, the best solution here is to try to locate one of your colleagues which has a bit more experience with this domain, or, if you can, to use some of our Professional Services in PTC to help you set this up - reach out to your sales person and ask him for this.
