Font DejaVu Sans - Bold

I have a problem with Adobe Acrobat reader. I receive a PDF document via email, I open it with Google Mail and the preview lets me read it well. I save it. But when I reopen it with Acrobat reader, the writing is just dots and an error bx tells me "couldn't find or find the font DejaVu Sans - Bold". I checked and this font is installed on my computer, for greater security I uninstalled and reinstalled it. Nope, the problem persists. BUT..... if, after saving the file from the Google Mail preview, I reopen it with a free program "I love PDF" the file reads well and reopening it a second time with Acrobat reader, it continues to read well. Do you have solutions?