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The local WACK test is optional. The local WACK tool will be affected by many reasons of the local device.. No matter the local WACK test failed or not, there will still be a online WACK test for your package. The store will only take the result of the online WACK test as standard. So the local WACK test failed is not a problem, but the online WACK test failed will be a real problem.
For secnarios like this, please try to upload the package to the Store to check the online WACK test and take that result as standard.
Just talk from the UWP side, there used to be many similar issues reported before. The local WACK test failed but the online WACK test succeed. So you are not the only one who meets this scenario.
Thank you.
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