FitNesse Tests stopped working because of malformed request string
<p>I am setting up FitNesse Acceptance tests for a SignalR hub application. The tests were executing and succeeding earlier this week. </p>

<p>Now I am getting an exception in the FitNesse execution window: </p>

<pre><code>WARNING: An error occured while fulfilling user request [fitnesse.http.HttpExcep
tion: The request string is malformed and can not be parsed]
java.util.concurrent.ExecutionException: fitnesse.http.HttpException: The reques
t string is malformed and can not be parsed
        at java.util.concurrent.FutureTask.report(Unknown Source)
        at java.util.concurrent.FutureTask.get(Unknown Source)
        at fitnesse.FitNesseExpediter.makeResponse(FitNesseExpediter.java:107)
        at fitnesse.FitNesseExpediter.run(FitNesseExpediter.java:60)
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.util.concurrent.FutureTask.run(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
Caused by: fitnesse.http.HttpException: The request string is malformed and can
not be parsed
        at fitnesse.http.Request.checkRequestLine(Request.java:159)
        at fitnesse.http.Request.readAndParseRequestLine(Request.java:73)
        at fitnesse.http.Request.parse(Request.java:61)
        at fitnesse.FitNesseExpediter$1.call(FitNesseExpediter.java:104)
        at fitnesse.FitNesseExpediter$1.call(FitNesseExpediter.java:101)
        ... 4 more
</code></pre>

<p>In the wiki browser it shows as:</p>

<pre><code>Testing was interrupted and results are incomplete. Test Pages: 0 right, 0 wrong, 0 ignored, 0 exceptions     Assertions: 0 right, 0 wrong, 0 ignored, 0 exceptions (21.689 seconds)
Could not complete testing: java.lang.Exception: FitClient: external process terminated before a connection could be established.
</code></pre>

<p>The tests run C# applications that subscribe to events on SignalR, post changes through a Rest API and verify that the expected messages are received.</p>

<p>I tried updating the Rest API and the Push API. I updated the FitNesse software to the latest version.</p>

<p>I am not getting any exceptions in the Windows Event Log when this happens.</p>

<p>Can anyone guide me as to how to find out what is going wrong?</p>