Ontario is a polymorphic, semi-stealth virus. It stays resident in memory and infectes all executed COM and EXE files. COMMAND.COM is infected by inserting the virus code to an unused part of the file.
Ontario will cause vague printer problems.
Two variants, 512 and 1024 bytes in size, are known.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
More information on 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.