so i recently restring my epiphone sg. ive bought it from a friend and its been used alot. in terms of road worn etc.

and now when i play , some notes dont work, they just create a buzz .

these notes are

on High E. 1st string, the 1,2,3,4,5th fret notes dont work.

on the B string, 5th note. You can also hear the buzz, but the note still plays
The strings are likely too low. Raise them, that usually does the trick.
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Did you restring the guitar with a lighter gauge of string than what was on there before? Sounds like the truss rod needs to be loosened slightly to get a little bit to get more relief in the neck.

Edit: It could also be a problem with the 6th fret being slightly taller than the others on the treble side. But then you would've most likely had the problem before restringing.
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