tracing in asp.net

I am trying to use the trace.axd viewer to view page traces. I changed the <trace enabled='true' > tag in web.config and all I get was
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Server Error in '/xyz' Application.
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Trace Error
Description: Trace.axd is not enabled in the configuration file for this application. Note: Trace is never enabled when

Details: To enable trace.axd, please create a tag within the configuration file located in the root directory of the current web application. This tag should then have its "enabled" attribute set to "true".










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Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832
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Turns out I have to restart the worker process in order to get it to work. Turning it off has no such problems though.