When using DesignSpark Mechanical on workstations connected to workplace or corporate LANs, make sure that your local IT adds the following URL to the whitelist items on their proxy server:
A proxy authentication bypass is ideal as it allows the DSM application to have direct internet connection for activation.
Also, add the following executables (EXEs) in the exclusions list for Windows Firewall:
They are located in the Program Files directory of your main Windows OS drive partition. For 32-bit computers, it's Program Files (x86)