The file backend_agent.dll is part of a plugin module made by Thunder Networking Technologies, LTD. If you get an error involving this file on your machine, we recommend you run a full scan immediately. Some programs associated with Thunder Networking Technologies, particularly their P2P software, are considered spyware. This file itself may not be spyware, but its presence on your machine could indicate you have some spyware installed.
In addition to our registry cleaner, ZookaWare PC Cleaner, ZookaWare also makes a spyware cleaner called SpyZooka. You can run a free scan with either product to check if you have any problems on your computer.
Most dll errors are caused by files being overwritten or moved. In the case of spyware, this can be a blessing in disguise. The errors can alert you to the existence of a malicious program on your machine, so you can take steps to remove it.