Can anyone please help about this error, running DNN 5.2.1

Server cannot append header after HTTP headers have been sent.

Description: An unhandled exception occurred during the execution of the
current web request. Please review the stack trace for more information
about the error and where it originated in the code.

Exception Details: System.Web.HttpException: Server cannot append header
after HTTP headers have been sent.

Source Error:

An unhandled exception was generated during the execution of the current web
request. Information regarding the origin and location of the exception can
be identified using the exception stack trace below.

Stack Trace:


[HttpException (0x80004005): Server cannot append header after HTTP headers
have been sent.]
System.Web.HttpResponse.AppendHeader(String name, String value) +2857733
DotNetNuke.HttpModules.Compression.CompressingFilter.WriteHeaders() +51
DotNetNuke.HttpModules.Compression.GZipFilter.Write(Byte[] buffer, Int32
offset, Int32 count) +21
DotNetNuke.HttpModules.Compression.WhitespaceFilter.Write(Byte[] buf,
Int32 offset, Int32 count) +133
System.Web.HttpWriter.Filter(Boolean finalFiltering) +8758019
System.Web.HttpResponse.Flush(Boolean finalFlush) +625
System.Web.HttpResponse.Flush() +20
System.Web.HttpWriter.WriteUTF8ResourceString(IntPtr pv, Int32 offset,
Int32 size, Boolean asciiOnly) +8651524
System.Web.UI.HtmlTextWriter.WriteUTF8ResourceString(IntPtr pv, Int32
offset, Int32 size, Boolean fAsciiOnly) +49
System.Web.UI.ResourceBasedLiteralControl.Render(HtmlTextWriter output)
+42
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer,
ControlAdapter adapter) +27
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter
adapter) +99
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer,
ICollection children) +134
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
System.Web.UI.Page.Render(HtmlTextWriter writer) +29
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer,
ControlAdapter adapter) +27
System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter
adapter) +99
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
System.Web.UI.Page.ProcessRequestMain(Boolean
includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1266