Introduction Logging serves as a cornerstone in the development and deployment life-cycle of any application. Serilog, a renowned logging library for .NET, offers robust features for logging messages to various destinations, including text files. However, deploying applications to IIS servers can introduce challenges, particularly pertaining to permissions issues that impact logging functionality. In this blog post, we'll delve into troubleshooting steps and solutions for addressing Serilog logging challenges in a .NET Core 7 application deployed to an IIS server.   Identifying the Issue Upon deploying a .NET Core 7 application utilizing Serilog for logging to an IIS server, you might encounter instances where log messages fail to be written to the designated text file. Upon investigation, it becomes apparent that the application lacks the requisite write permissions for the directory where log files are intended to be stored. This obstacle impedes logging functionality and necessitates corrective measures.   Troubleshooting Steps Review Logging Configuration: Commence by scrutinizing the Serilog logging configuration within your .NET Core 7 application. Ensure that the Serilog configuration accurately specifies the file path and logging sink for storing log messages. This step verifies that the logging setup aligns with the requirements of your deployment environment. Inspect File System Permissions: File system permissions are pivotal in enabling applications to write log files. Navigate to the directory designated in your Serilog configuration and examine its permissions settings. Confirm that the IIS application pool identity or the user account running the application possesses adequate permissions to write to the target directory. Grant Write Permissions: In cases where the directory lacks essential write permissions, take action to grant appropriate access rights. Depending on your deployment environment and security policies, you may need to manually adjust permissions or enlist the support of system administrators to ensure proper authorization for the application. Implement Log File Rotation: When log files accumulate rapidly, implementing log file rotation mechanisms can prevent log files from becoming excessively large. Configure Serilog to rotate log files based on size, date, or other criteria to maintain manageable log file sizes and simplify log file management. Validate Logging Functionality: Following the resolution of permissions issues and adjustments to logging configurations, conduct comprehensive testing to verify that log messages are being successfully written to the designated log files. Perform test scenarios that encompass various aspects of your application to ascertain logging functionality under diverse conditions.   Conclusion Effective logging is indispensable for diagnosing issues, monitoring application health, and troubleshooting errors in .NET Core 7 applications deployed to IIS servers. By adhering to the troubleshooting steps outlined in this blog post, you can address Serilog logging challenges stemming from permissions constraints and ensure seamless logging functionality in your deployed applications. Regularly reviewing logging configurations and permissions settings is essential to maintaining robust logging capabilities and facilitating efficient application maintenance and troubleshooting.