Hot answers tagged file-system
It's even riskier than cybersam says. You shouldn't check/repair a mounted filesystem (i.e. when it is in use), on any operating system, because programs might be using the files while you're checking them and possibly making changes. This could cause the checker to think there are errors where there are really no errors; it might cause unexpected behaviour ...
It might be that this option will try to repair any filesystem issues that it finds. If a repair attempt does not do the right thing, or is prevented from completion (say, the battery dies), you could end up with unusable files; or, if the repair attempt failed in the system partition, you could end up with a dead device (but you might be able to recover ...
Are you talking about Google Play Movies & TV? I think this is only for rented / purchased movies in Google Play. To play an MP4 file on your device, try an app like MX Player.
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