Are you able to select the text on your mobile? If yes, then a circular Copy icon will appear just above the selected text. What is the version of Windows Mobile you are working with? Please share the Security Details of the document.
I am unable to select text in the pdf document that I have a problem with (I am able to select text in other documents though). On long pressing, I just get a short pop up to add notes, but not to copy text, unlike other documents.
Model:Nokia Lumia 920
OS Version: 8.10.14234.375
Adobe Reader Version: 10.4.4
Here is the document I am trying to use:
The document is not write-protected and I am able to select text in the document on my laptop.
I tested the file and copying of content is working on PC/Mac but not on any mobile device.
The PDF file is created with some 3rd party application (calibre 1.5.0) and has hidden layers with it. I have shared that file with you after flattening it with Adobe PDF printer in private message.
Please test the file and let me know whether it working for you or not. I have tried it on iOS 9 (iPad Air 2), Android Lollipop 5.1.1 (OnePlus One) and Windows Mobile 8.1 (Lumia 920 specifically) and it is working on all the environments.
Let me know if this works for you.
Have shared a recording after using the unflattened pdf in private message. Don't knwo why exactly it isn't working still on my system.
I checked it again on a Windows phone and that copy function is not working. Earlier I tried it on a device which has modified ROM. So it seems to be an issue with this file on Windows Phone. I tried copying text on a different PDF file and it is working.
Too bad then, I guess there is no resolution for this issue then I too can copy text from some pdf's I have, but it fails on many. I think it might have to do with how the original pdf was created and a lot of other factors. Only strange thing is that the text can be copied on laptops etc. So there still might be some bleak possibility of getting to do the same on the mobile platform.