Exception: Not enough space on the disk

I added some code in the global.asax to log errors. Whenever I try to log the data to the App_Data\log.txt file, I get the following exception:


Error processing log error: System.IO.IOException: There is not enough space on the disk.
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at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.WriteCore(Byte[] buffer, Int32 offset, Int32 count)
at System.IO.FileStream.FlushWrite(Boolean calledFromFinalizer)
at System.IO.FileStream.Dispose(Boolean disposing)
at System.IO.Stream.Close()
at System.IO.StreamWriter.Dispose(Boolean disposing)
at System.IO.TextWriter.Dispose()
at System.IO.File.AppendAllText(String path, String contents, Encoding encoding)
at System.IO.File.AppendAllText(String path, String contents)
at Log.LogError(HttpContext context) in e:\web\elegancetec\htdocs\App_Code\Log.cs:line 39
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Does anybody know how to resolve this?</o>