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Close Outlook
Open Windows registry with tool regedit (Help)
Open the following tree path:
Code Block HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\Cache\
Delete the whole key "Extensible Cache" including all subkeys
Open the Cache folderRepeat the same with the LowCache folder:
Code Block HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\5.0\LowCache\
Delete the whole key "Extensible Cache" including all subkeys here too
Restart Outlook and check if it is working
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