In an effort to resolve issues with a failure to save changes when checking out a document that comes from Office, or is a PDF, the following steps may be performed:

Turn off "Protected View" in Office
1. Open an Office program (Excel, Word, etc.) and go to File, select Options.

2. Select Trust Center, then select Trust Center Settings.

3. Select the Protected View tab, then uncheck every box that displays, and select OK to apply the changes, then restart Office.

Turn off "Sandbox Mode" in Adobe
1. Open Adobe, select Edit, then select Preferences.

2. Under the Security (Enhanced) tab, make sure that "Enable protected mode at startup", found under Sandbox Protections section, is unchecked.

3. Uncheck "Enable Enhanced Security" under the Enhanced Security section, then select OK to apply the changes and restart the PDF program.