Trojan:W32/Packes is a detection name temporarily assigned to certain packed/compressed malicious programs that our unpacking engine cannot yet handle. When the unpacker code is created for that particular sample or file compressor, the malware will be renamed.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.