at what time is it best to change the strings on the guitar? i have my guitar for almost two years and since lately they don't stay in tune for too long, plus when i try to tune the guitar on the high E string when i pluck it i see A instead of the E but do u think that the tuner is the problem or my strings need to be changed
Dude this is sooooo wrong on many levels.

Use the search bar. and change your strings man
You haven't changed your strings in two years? I change mine every month. I think it's safe to say they need changing.
Main Gear:

ESP Eclipse CTM I
Dean 'Shards' Razorback
Chapman Guitars ML-1
Ibanez AEL40SE Acoustic
Blackstar HT-5 Mini Stack
EHX Metal Muff
EHX Small Clone
thanks for the help and sorry if this question was posted already.
Yea, def. change them at least once a month, it sounds a lot better, feels a lot better, i usually change once a month unless i do a lot of playing in which case i do it once every two weeks.
Alvarez Classical Guitar(don't know much about it).
Yamaha FG730S
Agile AL-2000 Black Cherry
Fender 25R Frontman Series II Combo
i like my strings abit roadworn, they just feel better, and keep tune better than new strings that often. i change mine about every 2-4 months, depending on how much i play, usually every 2 months,
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