"Tab"? You mean "Tags" yes? . View > Navigation Panels > Tags (four up from the bottom). . A PDF file will need to be open of course. If Tags is not on the menu then perhaps a 'repair' may help. . Help > Repair Acrobat Installation . If your installed Acrobat is at 9.1.2 then it would be good to apply each of the updates in order until Acrobat is at the current dot release (9.4.0). .
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View > Navigation Panels > Tags (four up from the bottom).
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A PDF file will need to be open of course. If Tags is not on the menu then perhaps a 'repair' may help.
.
Help > Repair Acrobat Installation
.
If your installed Acrobat is at 9.1.2 then it would be good to apply each of the updates in order until Acrobat is at the current dot release (9.4.0).
.
Be well...