Description

Occasionally support needs to request customers to gather SharePoint ULS logs to review and troubleshoot Foundation issues on the server side.  The below steps are needed to enable, capture and review the ULS logs.
 

Applies To

SharePoint 2010, SharePoint 2013, SharePoint 2016

Solution

If you are looking for the SharePoint ULS Logs,  the default path log locations are below:

For SharePoint 2010:
C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\Logs

For SharePoint 2013:
C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\15\Logs

Optionally, if you wish to change the location of the ULS logs, you can do so in Central Administration:
In Central Administration, click on Monitoring
Click on "Configure diagnostic logging" to alter the path to the diagnostic Trace Logs
To alter the usage logs, you can click on "Configure usage and health data collection" and alter the path for the logs under Usage Data collection Settings.

Additional Information

Overview of Unified Logging System (ULS) Logging
https://msdn.microsoft.com/en-us/library/office/ff512738(v=office.14).aspx