Highlight tool

Hi Carlosm,

As you said that the highlight tool is not highlighted, do you mean it is greyed out and you are not able to select it?

If that is the case, please try to repair the application and check if it is updated to the latest patch released.

To repair or to check if any updates are available, launch the application and go to Help menu.

Select Repair Installation or Check for updates from the drop down.

You may also refer this help document for more information on updates: Release Notes | Adobe Acrobat, Reader

If that does not help, let us know the dot version of the Adobe Acrobat Reader DC installed on your system.

To check that refer the steps provided here: Identify the product and its version for Acrobat and Reader DC

Also, share the OS version installed on your system.

Let us know if you have any questions.

We will be waiting for your response.

Regards,

Meenakshi