IIS 6 log file:
1. In IIS Manager, expand the local computer, expand the Web Sites directory, right-click the Web site which has problem, and click Properties.
2. On the Web Site tab, click Properties next to the Active log format list box.
3. Under Log file directory, you can check the logging path and the log file name.
4. Go to the path and find the log files.
IIS 7 log file:
1. In IIS Manager, expand the local computer.
2. Click Sites. Check the ID of your website from the ID column.
3. Click the web site which has problem. Double-click Logging icon on the Feature View.
4. On the Logging window, you can find log’s directory.
5. Go to the folder end with your website ID and find the IIS log files.