A lot of self-proclaimed "faith-healers" and "spiritualists" and "pirs" and other charlatans, swindlers, cheats and fraudsters who advertise in abundance in the newspapers amongst ethnic minorities in particular, they claim that they use "good magic" to combat "bad magic". To understand what is really going on, and what these people are doing, we have to understand that after selling his soul and his faith for a miserable price (see here), this is how a witch (that's what these people essentially are) performs his craft:

There are two things involved in an instance of magic:

The First: Al-Qaa'idah (The Base): This refers to that preparation (of magic) which may be a drink, or food which reaches the body through the stomach, or it may be what has been sprinkled on the doorstep, or the (talisman) buried in the ground, or put in flowing water, or planted somewhere. This is what is called "the base" and it is what essentially invokes the "khaadim" (agent, servant). You have to remember that the person performing this sorcery and witchcraft has already sold his faith, since he will only get agents from the Jinn performing and executing for him if they get something in return, which is disbelief (kufr) in belief, deed or word. Refer to this article to see how a man or woman becomes a sorcerer and acquires the assistance of the Jinn.

The Second: The Khaadim (Agent, Servant): This is from the devils amongst the Jinn. And this agent executes whatever is found in "the base", and this agent understands its symbolism and coding. The devils amongst the Jinn venerate the talisman (spell) and the devilish names it contains, either written explicitly or in coded form (which are likely names of the senior of the Jinn, and their kings and the likes). After preparing his "base", the magician will say something like "O servants (agents), you are entrusted through these talismans or spells to separate between so and so and his wife" (or whatever the magic might be for). Now, the agent from the Jinn, out of his veneration for what is in the talisman (of the lofty names), will then begin his work on the one on whom the magic is intended, and it is likely that this performing agent may simply be commanded by more senior Jinn.

So one sorcerer will perform an instance of magic on, let's say a man to separate him from his wife. Now this man may go along to someone he believes is "religious" and is going to help him. So he goes to him, and this man promises to help him, and this man (the "healer") in reality practices magic, even if he makes an appearance of religiosity. What this sorcerer (in reality) will do is to include some apparent religious aspects such as ask the man to read parts of the Qur'an or other incantations which in and of themselves are fine. However, to get rid of the magic and to make his money quickly, he will perform another instance of magic on the same man. But he's got to make sure that the "agency" from the Jinn he is going to invoke and use is of a higher authority than that used in the first instance of magic. It's essentially like a turf-war. So initially the first instance of magic may disappear but then the effects of the second instance of magic (which maybe something totally different) will begin to manifest. What happens is the second "agent" (from the Jinn) comes along and kicks out the first "agent" (from the Jinn), so the first magic goes and appears to be "healed", but then the second instance of magic will commence shortly thereafter. And this person simply becomes a playground for the magicians and this is how people get used and abused.

As for whether the magic takes effect or not, then all of that is subservient and dependent upon Allaah's will and decree, and magic (the combination of "the base" and the implementation by "the agent") is simply a means (sabab) through which the effect may be attained if Allaah allows it to take place. However, there are many factors (which arise and are determined through Allaah's permission, will and decree) that will prevent it from taking place such as the strong faith and practice of the individual, the protection through recitation of the Qur'an and the remembrances, the use of ajwaa dates, drinking zam zam water maintenance of wudhoo and so on, or just the pure will and decree of Allaah alone, without the need for the coming together of one or more asbaab (means) - and indeed sufficient is Allaah for the one who relies upon Him alone.

Treating Magic with Magic is Unlawful (Haraam) and Is from the Handiwork of the Devil

The Scholars of Islaam have declared it unlawful for magic to be treated with magic, and it is related from al-Hasan al-Basree (rahimahullaah) that he said, (لا يحل السحر إلا ساحر), "Magic is not repealed except by a magician" and what he means is that whoever repealed magic through magic (through the use of anything considered "a base" as explained above), then this person is no doubt a magician and a disbeliever in Allaah - so long as whatever he is doing is not from the Book or the Sunnah.

And there occurs the chapter in "Kitaab ut-Tawhid" (the Book of Monotheism) in relation to what is called "an-Nushrah" which simply means the treatment of magic with magic, this is how it was understood with the Arabs in Jaahiliyyah, and so the following hadeeth is found in the chapter on "an-Nushrah":

From Jabir (radiallaahu anhu) that the Messenger of Allaah was asked about an-nushrah,so he said, "It is from the actions of the devil". Reported by Ahmad with a good chain and Abu Dawud.

And this is in reference to magic being treated with magic. But the word "nushrah" actually means that a man simply stand up having been cured and relieved (of his ailment), this is the actual meaning of "nushrah", and thus "nushrah" (healing) can be by way of what is legitimate, which is through the proper Sharee'ah means of treating magic, or it can be what is mentioned in this hadeeth, which is through the action of the devil, which is another instance of magic. And the Scholars use this hadeeth as textual evidence for the express prohibition of treating magic with magic.

So from this, we learn that there is no such thing as "good magic" combating "bad magic", that is a lie and a swindle, all magic, which inevitably requires the agency of the Jinn, involves kufr and shirk and obedience to the devils. To keep the perspective here go and read this article - and you will learn that Iblees and devils amongst the Jinn have enmity to Aadam and his offspring, and Iblees desires to be worshipped, the devils desire to be worshipped, since they envy Aadam and his offspring, for Iblees was ordered to prostrate to Aadam, but he was arrogant and refused. So the devils amongst the Jinn want worship, and the magicians are prepared to worship them and to sell their faith and to commit acts or statements of disbelief and other vile acts. And thus it is not possible for anyone to indulge in magic except that he must have won the assistance of the devils, since there is no magic except with the assistance of the devils.