O97M ("Office97Macro") is the family name of all Office 97 macro viruses. These viruses are able to infect two or more Office 97 applications. For example, O97M/Tristate is able to infect Word, Excel and PowerPoint files.
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.