Before viewing PDF documents in this browser you must launch Adobe Reader and accept the End User License Agreement, then Quit and relaunch the browser.

Uninstall Adobe Reader. Safari will read PDF's just fine without it.

When you install Adobe Reader it takes over all viewing of PDFs without asking, unless they've changed it.

You can open Adobe Reader and set the preferences to not take over the Browser. At that point you can accept the license agreement (well, you'll have to in order to get to the preferences).

If you actually need Reader, you can adjust the preferneces. If not, get rid of it as arthur suggests. There are very few PDFs that Preview cannot render. That would be the only reason you need it.

Uninstalling the reader isn't necessary. If that's your preferred app for PDFs, than go ahead and follow the instructions.

It seems, Adobe Reader is, probably, set as your default app for PDFs. You can, easily, change that. Right click on a PDF file and select "Get Info". Near the bottom of the pane you'll see "Open with:". From the pull-down menu select the application that you want to use to open this file type. Click the "Change All..." button the make this setting global. Your Mac's built-in PDF viewer is Preview. Then, try viewing the PDF in Safari. It should work just fine.

Back up all data.

If Adobe Reader or Acrobat is installed, there should be a setting in its preferences such as Display PDF in Browser. I don't use those applications myself, so I can't be more precise. Deselect that setting, if it's selected. Otherwise do as follows.

Triple-click anywhere in the line of text below on this page to select it, the copy the selected text to the Clipboard (command-C):

/Library/Internet Plug-ins

In the Finder, select

Go ▹ Go to Folder

from the menu bar, or press the key combination shift-command-G. Paste into the text box that opens (command-V), then press return.

From the folder that opens, remove any items that have "Adobe" or “PDF” in the name. You may be prompted for your login password. Then quit and relaunch Safari, and test.

The "Silverlight" web plugin distributed by Microsoft can also interfere with PDF display in Safari, so you may need to remove it as well, if it's present. The same goes for a plugin called "iGetter," and perhaps others.

If you still have the issue, repeat with this line:

~/Library/Internet Plug-ins

If you don’t like the results of this procedure, restore the items from the backup you made before you started. Relaunch Safari again.

Thanx, that worked for me.

Except, there's a capital I in "Plug-Ins."

LoL. just go to application, open adobe reader and accept the agreements. 2 sec to solve.

In my case, at least, it happened every time I read a PDF document in the browser. Accepting the agreement in Adobe Reader didn't help. It just repeated the request to accept the agreements.

Yeah thanks, deleting adobe pdf viewers that were in this folder solved my issue.

Everyone beware, even if you delete adobe reader app, adobe pdf viewing plug-ins can remain in this internet plug-ins folder.

This was a very good explanation; now safaris is showing the pdf!

I think the reason was that I haven't the reader but the Pro version from the Creative Cloud

Thanks Linc - been driven crazy with this for weeks and have been logging on to my Microsoft laptop each time I need to view PDFs. Just tried out your suggestion and it's fixed! Thank you.

I had the same problem, but only when trying to open a pdf from a Chrome browser window. I tried various options to change preferences and so on, but none of them worked, so I decided to try opening the document from the Safari browser and it worked. I was able to open the document without any issue and without the "Before viewing PDF documents in this browser you must launch Adobe Reader and accept the End User License Agreement then quit and relaunch the browser."message.