i can't make a software update it says my device is modified

[Android Central Question]

When I go to Software Update, gives me a message "The operating system on your device has been modified in an unauthorized way. Try down-loading software updates using Smart Switch on your computer or visit a customer service center." I never rooted my device, and when I go to root checker apps, they all say I'm not rooted. So what's the problem? But when I go to "Status" in settings in "Device status" it says Custom. So what does this mean? I never rooted my device, so it should have been saying "Official". Any answers?

 

[tony bag o donuts]

Did you buy the device new or used? Is the bootloader unlocked?
Which device, not just the model name but under about device it should list it.
What OS are you currently running?
Any apps that were sideloaded?
Did you try a master reset? It will wipe everything.
Best bet is to take it to a store first.

 

[Andr0id Use3r]

I got the device used,
the device is samsung galaxy j7, 2015 model
there were apps sideloaded,
haven't tried a master reset.

 

[Andr0id Use3r]

btw I sent the question, and my os is android version 6.0.1

 

[tony bag o donuts]

I got the device used,
the device is samsung galaxy j7, 2015 model
there were apps sideloaded,
haven't tried a master reset.

You will have to unroot your device to get the proper over the air updates.
Read about it here:
https://rootmygalaxy.net/unroot-unbrick-samsung-galaxy-j7/

 

[Spawnlives]

I got the device used,
the device is samsung galaxy j7, 2015 model
there were apps sideloaded,
haven't tried a master reset.

Device status saying custom means your phone has been modified which means your Knox has been tripped. With a tripped Knox you will not receive OTA updates again and will have to do manually.
You can check Knox status in download mode.
Factory reset,flashing firmware will not fix a tripped Knox.
Side loading of apps does not trip Knox.