Assuming you're talking about a USB hard disk, SSD or memory stick (not about a printer, mouse, keyboard or camera), can you tell:
1. How many partitions are on the drive
2. In what file system they are formatted (see properties of the drive letter)
3. What file systems are supported by that TV (see the user manual)
What you need to do depends more or less on the answers to this questions.
Kees
I have just purchased a LG smart TV model 49UB850V. I'm not techno minded and seem to be having problems connecting a USB. I keep getting an error message saying " unsupported file system need to connect the device formated by windows OS" What do I need to do, any help would be appreciated. (In laymans terms if poss 
Many thanks
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