Since the official activation servers are offline, there is no magic fix that brings them back. However, depending on your error type, you can try the following legitimate methods.
For many versions of TotalMedia 3.5 (specifically the "Theatre" and "Extreme" variants), the license key can be inserted manually into a configuration file. This bypasses the need for the software to communicate with the defunct activation server.
Steps:
Many laptops (like Dell or HP) came with a pre-installed OEM version of TotalMedia 3.5. Those keys often only work with that specific manufacturer’s recovery disc.
ArcSoft was acquired by Corel in 2014. All legacy products, including TotalMedia Theatre 3.5, were discontinued. The online activation servers that validated your license key are permanently offline. If you reinstall Windows or move to a new PC, the software cannot "phone home" to verify the key.