Unable to create a pdf from scanner

While I love Acrobat DC, I do not like how they rely upon Apple's Image Capture for doing the scanning. Since you have the HP Color Laserjet scanner, which I assume came with it's own software, here's what I strongly suggest:

Open up your scanner's software, (since I do not know this software, I cannot tell you go to where the following features are, but look around and I'm sure that you can find them (or something equivalent).

Set the scanner to save your scans as a TIF document (not jpeg). Locate where you want the scans to end up.

Do a "location" scan on the first document, this is where you set your margins. You can also set the level of gray your background will be at this point. This is BEST done using a Levels adjustment. I've done a screen capture of one from Photoshop, they all look very very similar.

Here's the issue, most scans you will do of paper also shows the text behind the page you are scanning. You probably want to remove that as well as any gray tint the page itself has. When you open up the Levels adjustment tool, if you look at the bottom right of the histogram you will see a white slider. This is currently pointing at the most white an 8-bit image can produce. If you slide that over to the left while looking at your image, you will encounter a very steep black histogram high point and you want to continue until you have almost past that point. What you are effectively doing here is telling the software that that point is where you want the software to think that that "gray" point is to be considered white. You may also want to fiddle with the black and midtone adjustment to sweeten the image's look. Now do the final scan on this image.

Assuming that you are going to be doing scans from the same document and they all are the same size and have the same color/hue tint, at this point you can simply lay your images on the scanner and only do the final scan on each image as you will not need to set the margins nor the grayscale correction. Do not worry about the name of the document as you will probably be getting things like "image1.tif," "image2.tif," "image3.tif," etc. This is good.

Now select all of the final images and drag the whole group of them onto Acrobat's icon in the Dock. You will probably get a message asking you if you would like to join all of these images into one large document. Click "Yes." Now you'll be asked if you want Acrobat to do the OCR of the pages in this document. Again, click "Yes."

Now (depending on how many pages there are) go get a cup of coffee or something and when you come back your document might be ready.

The big reason why I prefer this approach over letting Acrobat use Image Capture is that Image Capture does not have a Levels adjustment. There is no way to fix that issue but in any reasonable scanning software, it's a minor extra work option that will tremendously help your final product.

Let us know if this works for you,