When calling CloubQueue.GetMessage(visibilityTimeout, callback), an exception is raised with a bad querystring format error.

The bug is in the CloudQueue class in the InnerGetMessages(messageCount, peek, visibilitytimeout, callback) method :

Line 367, replace :

                var visibilityQueryString = visibilitytimeout.HasValue ? string.Concat("visibilitytimeout=", visibilitytimeout.Value.TotalSeconds) : string.Empty;

With :

                var visibilityQueryString = visibilitytimeout.HasValue ? string.Concat("&visibilitytimeout=", visibilitytimeout.Value.TotalSeconds) : string.Empty;

That fixes the issue.

HTH
Yacine