Which of the following issues is least likely to arise during a 3CX installation?

Exceeding the license limit for users is least likely to arise during a 3CX installation because licensing is typically one of the first considerations during the installation process. Before proceeding, administrators usually verify their licensing to ensure the number of users or extensions can be accommodated. This proactive approach minimizes the possibility of encountering issues related to user limits during installation.

In contrast, firewall settings conflicts, network configuration errors, and compatibility problems are common and can occur unexpectedly. Firewalls might block essential ports needed for communication, and misconfigurations in the network can prevent proper connectivity. Similarly, hardware and software compatibility issues can arise if the system requirements are not met or if there are incompatibilities with existing infrastructure.