Once you have received a registration issued by the EUIPO, you are legally protected against third parties applying to register a similar mark in a similar field of business. In this case, you can object directly to the EUIPO by submitting a notice of objection.
Most importantly, you have legal protection against any infringer - any competitor using your trademark without your permission. In this situation, it is advisable to send a cease and desist letter and make the violator aware of the possible consequences.
Depending on the circumstances of the crime, you can try to reach an agreement with the opposing party by way of mediation or complain directly to the competent civil court with legal representation. If the trademark is registered by the EUIPO, the competent national civil court of an EU member state is entitled to order enforcement measures to prevent infringement in all EU member states. It should be noted that these measures can anticipate legal protection even before the final decision, since the competent civil court can also issue effective temporary injunctions in other EU countries.
Often the concept of trademark infringement coincides with the crime of counterfeiting, but not all trademark infringements can be considered counterfeiting.