It's almost impossible to change the size by accident. It's hard to do when you want. How are you checking it?
I was trying to reduce the file size to make the upload to Create Space. This page size was somehow changed in that process, but I didn’t know it until I uploaded. When I got the file size in the range I uploaded. This went okay. I found out the pages were 13 7/8th x 10 when the automatic reviewer showed me the pages were off. I designed the book at 6x9. In addition, I found I can check the pages size of the book in when I open the PDF in Acrobat. I do this by right clicking the opened document, and the page size shows in in a dialogue box under properties, then by clicking the description tab one sees the page size.
Any fix ideas?
We can't tell you how to “fix” the issue if you can't tell us what exact steps you took to get to the current situation.
There is not function within Acrobat that implicitly changes page sizes. Anything that changes page sizes is very explicit. Examples of this are (1) the Change Page Size feature of the Set Page Boxes print production tools and (2) some fixups available under Acrobat Pro DC's Preflight tools.
By the way, each page within a PDF file can have its own page size, the page size indicated in the Document Properties may not reflect anything all that useful.
You might also assist us assist you by providing more information about how this PDF was created and from what application and exactly what you have been doing with it in Acrobat. There are certain types of edits and manipulations for which Acrobat is well suited, but it isn't a layout program/editor or a comprehensive prepress suite.
The PDF proof Create Space sends for review is, in fact, a two-page spread. This size might be including the gutter and the trim marks and 13 7/8 x 10 might be how a 6x9 book would be configured. I have been focusing on the page size and that might be explained, and not the problem. The rejected proof shows the pages all messed up. I did nothing to actually change the page size. I sure as hell tried to get it back to 6x9 with no luck.
I only know the rejected proof has the pages wrong in number, size, and area showing the content.
You are still not providing any more information. Here is what Dov asked for:
You might also assist us assist you by providing more information about how this PDF was created and from what application and exactly what you have been doing with it in Acrobat.
Unless you can explain how you created the PDF file, there really is nothing we can do to assist in fixing this problem. What application did you use to create the file? How did you configure the page size of 6x9"? Did you verify the page size before you did anything in Acrobat? Based on everything you've heard so far, you can assume that it was wrong to start with. What exactly did you do in Acrobat? Which Acrobat version are you using? On a Mac or on Windows?
When you go into Acrobat DC's preferences, then go into "Pager Display", there is an "Always show document page size" option:
When this option is on, you can then see the page size being displayed in the lower left corner of your page:
To make things a bit more complex, there are actually a number of different sizes that can be associated with each page. You can see that when you bring up the Set Page Boxes tool (in "Organize Pages" in Acrobat DC):
As you can see, you can change the Crop, Art, Trim and Bleed box this way, there is also a media box, which is the largest of these page boxes. Usually, the crop box is what determines what is shown on the screen and printed, but printers are often also interested in the other page boxes. You need to find out from your print provider (I am not familiar with Create Space and their requirements) what exactly they are looking for.
Once you report back with answers to the questions above, and information about the page sizes that are reported by Acrobat on a per page basis, we might be able to help.
I’ve just resolved this problem with Create Space. Dov’s hint about size was the key to locating the problem. The proof I sent was showing both pages. I didn’t change anything. This freaked the automatic system. The help person at Create Space fixed this by exporting the book to a clean 6x9 word document that I can download, fix, and change back to PDF. Thanks, Bill