What is DataStore.edb?:The DataStore.edb file is some kind of log file, it keeps the history of Windows updates and it is located under SoftwareDistribution folder (C:\Windows\SoftwareDistribution\DataStore\DataStore.edb). Its size will grow for every Windows Update check.
Is it safe to delete?:Yes, it is safe to delete, but the next time when Windows checks for updates, it will basically start from scratch and check everything. There's no point in deleting DataStore.edb since it will just be rebuilt the next time Windows checks for updates. If you are just looking for stuff to delete you can empty the SoftwareDistribution\Download folder.
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