Geolocation reports (Top Countries by Visits) built in Experience Analytics might contain the following labels: Unknown country, Unknown region or Unknown city.
Additionally, the following warning might appear in the log files of the Content Management server:
WARN [Experience Analytics]: Could not resolve dimension key for country: 'xx'
(Where xx is a lowercase contraction of location name).
Download and apply the patch for the relevant Sitecore XP version: Sitecore.Support.253023. See the readme file inside the archive for installation instructions.
To get a patch for Sitecore XP versions that are not listed at the provided link, contact Sitecore Support.
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