The steps that you need to take:
1. We recommend you to also unplug the machine from the network in the eventuality that the situation will escalate.
2. Please perform an in-depth scan using a strong antivirus. Alongside, also perform a scan using an antivirus software you have at your disposal.
3. While the scan is performed, open the process that is shown as being the source of the problem and try to find the issue:
- If the process shown is a browser (70%+ cases) then the problem might be extra toolbars or other browser, gadgets or third party software that is installed in the background with other software.
- If there are unwanted extensions and tollbars please remove them/ uninstall them. Make sure there is no unknown/unused/unwanted software installed in Control Panel>Programs and features.
We recommend you scan these endpoints with a reliable antivirus as soon as possible.
For further assistance please contact firstname.lastname@example.org