Hi and Welcome. My Name is ***** ***** I look forward to assisting you today with your question.
How did you clear the Gallery settings ?
Are you using the Email application or Gmail application ?
I want you clear the data for these apps. Go to Settings > Applications > Application Manager and swipe to All tab. Then find Email app. Then Force Stop. Then Clear Data. Remember, this will clear the Email application (you may need to setup your Email again).
Then find Google Services Framework. Clear Data. Restart your phone and check if you are able to download the attachment.
Please let me know if that didn't work, so we can continue troubleshooting.
Can you delete the email account and add it back and try again ?
Also when you tap and hold down the attachment icon, what do you see ?
Have you tried deleting the account and adding it back ?
Ok, let me know how it goes.
Do you have this problem with that particular attachment ? Can you send a photo from your phone to yourself (to your own email address) and are you able to open it ?
Also download Outlook from Play Store and setup your hotmail account. Then can you open the attachment with that Outlook app ?
Goto Application Manager > All Tab and do you see Downloader or Download Manager there ?
Force stop it. Then Clear Data and disable it. Restart your phone. Does Play Store work now ?
I believe it is the Android system that has the problem. Can you connect it to different WiFi network and see if you are able to download from that network ?
If that didn't work, then we have to backup the phone to your computer and do a factory reset. Factory reset will install a fresh firmware on it and that should fix the problem. Then you can restore your files back to it from your computer.
You can backup using Samsung Kies application --> http://www.samsung.com/in/support/usefulsoftware/KIES/
But first, try it on a different WiFi network and let me know the results please.