Unfortunately, this forum does not support attachments, and I'm presuming that you attached the file you're trying to read to an e-mail message you posted to the group. If you can upload the thing to any form of cloud storage that allows those supplied with the link to download the file that would be a good workaround.
I'm also pasting some advice I got from Freedom Scientific Technical Support a couple of months ago related to PDF files. Although I know you're not using JAWS a lot of what's mentioned is more generally applicable.
This is an Adobe Reader setting that is causing this to take place. If you walk through the instructions below, you can change this setting:
A. Using the Accessibility Set Up Assistant
When you launch a PDF the first time, the accessibility set up assistant opens. If the accessibility wizard has already run, do the following to open it:
1. Press ALT+E to open the Edit menu.
2. Press Y to select Accessibility submenu.
3. Press ENTER on Set Up Assistant. The first page of this five page dialog box opens. The default choice is fine, press ENTER to move to the next page.
4. On the second page you can change things if you wish, but by default it is OK. Press ENTER to move to page three.
5. On the third page you can change things if you wish, but by default it is OK. Press ENTER to move to page four.
6. On the fourth page, if you want to use the list of links, list of headings, and the JAWS find command so on to access long documents, change the radio button from
"For large documents, only read the currently visible pages"
"Read the entire document at once."
If you do not make this change, in long documents JAWS only sees the links and headings on the current page. Additionally, JAWS can only search the current page with the JAWS find command. If you do select read the entire document at once, it may take a few seconds longer to process large documents, but it is worth it to be able to see the links and headings in the entire document, or to search the entire document with the JAWS find.
7. Press ENTER to move to page five of the Set Up Assistant.
8. If the check box for Reopen documents to the last viewed page is checked, you may want to uncheck this. It is a personal preference. TAB through until you reach the check box for "Display PDF documents in the web browser," and uncheck it.
9. Press ENTER to activate the Done button.
B. Additional changes in Adobe Reader XI preferences.
1. Press CTRL+K to open the Adobe Reader XI preferences.
2. In the Categories list on the left side of the dialog box, choose Accessibility.
3. Press TAB to move to the item, Show Portfolios in Files mode (not checked by default) - check this.
4. Press TAB to move back to the Categories list and choose Security (Enhanced).
5. Press TAB to move to Enable Protected Mode at startup (checked by default) - uncheck this.
6. Press TAB to move to the OK button, and activate it with the SPACEBAR.
NOTE: The option to view PDF documents in the browser is no longer found in the Preferences. You must use the Set Up Assistant to find this
Never underestimate the difficulty of changing false beliefs by facts.
~ Henry Rosovsky