You must encounter the problem of lost tab on ribbon and navigation bar in Outlook 2016 because of a possibly incomplete and incorrect installation of any application. Incomplete and incorrect Outlook installation interrupts the functionality and features of the device. There a few solutions on managing lost tab in Outlook available at www.outlookhelp.support.To resolve lost tab problem on ribbon and navigation bar in Outlook, you must try a few steps that are described here. First, you need to shut down Outlook and go to the app data "%appdata%\VeranoSoft\Categorize Plus\Settings" folder.
Rename the "Settings.xml" file to some other name. After this, go to the "%appdata%\VeranoSoft\Categorize Plus\Settings\Backup" folder. Delete the "Settings.xml" file. At last restart Outlook. If the ost tab issue on ribbon and navigation bar still persists in Outlook 2016, you better contact Microsoft Outlook Support Phone Number. This support number from Microsoft Outlook help customers real time and fixes Outlook 2016 lost tab issue and other problems.
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