Introduction:CAPI2 traces are part of windows OS and can be enabled from event viewer section. Very useful when we deal with SSL/TLS connectivity or client certificate validation issues. To enable: 1. Open Event Viewer 2. Navigate to Applications and Services Logs -> Microsoft -> Windows -> CAPI2 3. Now, remember that this utility captures all the key aspects of SSL/TLS handshake or failure from the complete system. So we need to enable/disable as soon as we complete the issue repro. 4. To enable/disable, we can right click on "Operational" setting and select enable/disable respectively. Log Size: 1. By default CAPI uses a ring buffer mode of 1 MB file size. 2. Once logging is enabled we can modify the default 1 MB file size and can even avoid override and force it to create new files. (useful for intermittent errors).