why are highlight and comment tool grayed out for some documents? (Adobe Reader XI)

[ChanKim]

I'm reading many PDF documents these days.

Today, I found for most documents, comment and highlight tools work, but for some other documents they don't(those tool menus have been just grayed out).

What makes this difference?

[ChanKim]

I compared two files. The highlightable one was made be 'Microsoft Word 2010 in 2017, but the non-highlightable one was made by Acrobat PDFMaker 10.1 for Word in 2011. Maybe the older one doesn't support highlight or comment. If we can upgrade the older document for newer format, maybe it would be possible to use highlight or comment tool. Just my guess..

[Matthew5ED8]

meet.google.com/msg-rkoo-hyh

[JR Boulay]

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