While TeamViewer Endpoint Protection was scanning the Outlook archive(.pst or .ost) it detected one or more attachments as malware and marked them as Infected.
Malware sent in Outlook is fairly common these days. Small and Medium-sized businesses receive many targeted or mass malware campaigns on a weekly bases.
Historically Microsoft improved Outlook to allow Security Vendors to be able to clean malware in Outlook archives however, due to old implementation on how OST and PST works on a Windows system removing malicious attachments is sometimes not possible.
The possible causes for when Malware cannot be removed from Outlook archives (.pst or .pst) are:
We are always improving our methods dealing with Outlook malware as attachments in the OST and PST archives and we rely on your feedback and reports to further improve it.
You can perform the following actions to clean/remove the infected malware attachment from Outlook.