Step 1: install certificate
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a. double click on keepitsimplesoftware.cer
b. click on install Certificate.
c. select Local Machine.
d. click next.
e. click yes to do you want to allow this app to make changes to your device.
f. click Place all certificates in the following store.
g. click browse.
h. select Trusted Root Certification Authorities.
i. Click OK.
j. click next.
k. click finish.
l. click OK
m. click OK

Step 2: install software
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a. double click on keepitsimplesoftware.msix
b. click on install
c. click on the close button or launch button.