What should a CS manager do when the customer is totally against the refund / exchange policy of the company?

It totally depends on the situation and the customers and the product.
I understand that there are some customers that are very hard to satisfy, but some customers as also too valuable to be lost.
In my opinion policies are usually set as guidelines and at certain levels policies are usually broken "within limit" to maintain a valuable customer.
If there is no company loss and the product can be resold, I say escalate the complain to someone who have the authority to break the rules.
I'm sure the customer in that case will come back with more business.
Again I repeat it all depend on the situation, use your best judgement and you will be fine

depend on customer history with the company if traceable or not, decision should be linked to potential loss to the company from such customer and weighting the loss fro m the refund that might incur the business vs.
losing customer future spend.
Unfortunately, in the ME region, we take customers for granted.
However, Dubai for example have set consumer right protection and most companies need to be familiar with that in accordance to own company policies and standards.
its not always good to hide behind the policy for the future of the business and its growth.
M&S is one of the best in customer service and even though they face lots of refunds and return of goods, yet they are scored the best choice for purchasing from among retail shoppers.
ASDA, 2nd largest retailer in the UK, they refund any purchase of nonfood items with invoice of less than 100 days..! retaining satisfied customers is like gaining new partners who keep spending more and more..
its all about the math's behind the level of long term loss..

If the customer is too valuable to you i would take the extra mile of trying to re-sell the goods to the first coming customer.
Provided that the support or waranty will be extended to the new customer.

if he can resell it again without losing for the company he have the power to return but i preffer the exchange only if its sellable

The company has set policies and standards and those policies and standards exist to protect the company.
Typically such a policy is a risk mitigation strategy.
There will always be customers who are not pleased with a policy.
It takes significant time to continuously alter policies.
Usually those policies not only protect the company but the consumer.
It protects the company against false claims and monies lost as a result of those claims.
In the scenario given, the customer should be made aware of the policy prior to completion of the purchase.
Before signing the final receipt the consumer must be aware that his or her signing indicates that he or she understands the policy and will abide by that policy.
He or she has the right to protest before leaving with the purchase.
The liability lies with the customer at this point.
If the customer comes back after that, he or she has no standing to argue.
As a customer service manager, you should activate appropriate customer relations strategies and find out the source of the customers issues.
If it is a manufacturing flaw then you can tell the customer you will pass along the complaint but remind the customer that the policy is still in effect.
However, given the situation you will see if an exception can be made.
Make no promises.
Remind them about the reason for the policy.
If the customer is simply dissatisfied because he or she changed his or her mind after signing the receipt, then you are not obligated to make an exception.
Remember you want to keep integrity within your company.
You want your customers to respect your business and its policies.
In such a case the policy should be re-explained to the customer and if time permits the reason for the policy as it stands.
The customer should be reminded that this policy was stated prior to final purchase and the customer signed in agreement.
The policy should not be altered because one customer has a complaint about the standards as they are set.
If it is allowed too often then you will end up with multiple problems in this regard.
You have to know your customers and you have to understand your company and what lengths you will go to protecting your company.

A CS Manager should listen and explain the case to the client at first and then he should be politely firm with the client especially on respecting companies policy if the client already knows the policy If still insisting not to accept it.....in that case then he should politely apologize to the client's request .

First, CS Manager should convey him/her about the policy and procedure.
And then listen to his/her requirement again.
Politely convince and if still not understanding so try to adjust customer according to the situation because it usually depends upon the situation.
Variation and fluctuation is always there in terms of policies and procedure of the company.

Generally, a CS Manager should be always be very careful while handling customer complaints, especially, when the customer is agitated, because, the PRIME of any business is CUSTOMER RETENTION, through GOODWILL, there is no other SHORTCUT.
The CSM should weigh the situation: Losing the customer, once for ever {OR} considering a small loss now {AND} recover more than that loss, vide future business from that customer It may be very tricky situation: The CSM, first and foremost, should analyze the situation in the light of the existing company policies, procedure and protocols.
It is very vital.
Then try to explain the same to the customer and convince.
Ultimately, if the customer is very adamant in his stand, then, depending upon the prevailing situation, should take a deviation, to the extent possible.
Here, the main thing that may clinch the deal is the politeness and patience borne by the CSM during the entire upheaval.

Each establishment have  their terms of service.
If a customer is right in his or her  demands, i think to  sustain the pedigree of the establishment, refunds should be made.
But if its against the companies  terms of service , the custome should be made to understand why he or she has to  comply

it depends on situation.first of all give him smiling face and try to ocalm him down.and try to help the customer in every way possible.if there is any loophole in companys exchange or returns policy and customer is longterm customer .you can try to accommodate him.otherwise you have to explain him company policy and apologize to him for this in a nice way.

I think there is a manger, who can break the rules.
The policy isn't forever, we can change it once, when the situation so difficult and when we will lost this customer.