I'm unable to open email attachments on my Samsung Android device. How can I fix this?

There are several ways to solve this issue. You can download related apps, remove and add back your email account again, or perform factory reset. Please choose one of the methods.  

If you cannot open an E-mail attachment, please consider downloading relevant applications from Play Store.

You may also try to remove your E-mail account and add it back again. 

If you use third-party email app, you can simply install the apps and set up the account again

If you were not using a third-party email app, you can follow the steps below.

Care!

Performing Factory Reset will erase all data from your devices.

Factory data reset allows users to delete all data stored in the mobile device. You can make backup copies of the data before performing the reset (How do I Back up my data?). Samsung is not responsible for any data loss. 

This guide introduces how to reset your mobile device when the device operates normally and when it is not responding. Please follow the steps below for factory data reset.