customer service

[anatta]

What is the best and easiest way to solve the customer's complaints?

[Oneeyedvic]

identify the exact problem

[redcrx]

give them what they want :)

[factor-fiction]

Don't let the problem arise in the first place
Put yourself in the customer's shoes... or imagine it was your son/grandmother etc with teh complaint
Listen to teh customer, echo back what they say, empathise, find out what they expect, say what you will do, then do what you promise.
Put in place actions to prevent same problem recurring

[Marg0]

At least verbally take their side, even if you are about to go against their wishes. Don't argue with them.