Microsoft’s Windows Phone app rankings have been stuck for around two weeks, prompting angry responses from developers.

The issue first started on around May 18 says one WinRumors reader. A developer based in Italy, who wishes to remain anonymous, says the Windows Phone Marketplace ranking system has been frozen for around two weeks. “Marketplace visibility entirely depends on ranking,” he says. New applications will “never surface to the public” he adds. Microsoft’s ranking freeze hurts developers as any rankings do not get recorded in the initial phase of the app or game release, an important way for other Windows Phone users to discover apps.

Windows Phone developers have taken to Microsoft’s forums to complain about the issues. Unfortunately some Microsoft support personnel have deleted the threads or simply stated that the App Hub does not look after the Application Rankings. “One or two days would be bad enough,” says the developer. “Ten days and not even an answer, it’s making me and other developers anxious whether this platform still needs a lot more maturity.”

One thread, created on May 27 and remains alive at the time of writing, was started by Elbert Perez. U.S. based Perez recently went full-time developing Windows Phone 7 apps. Perez revealed last week that his total revenue so far from creating Windows Phone 7 apps is nearly $30,000. “The App rankings have been stuck for 1 week now and I have not seen any official response from Microsoft on this,” said Perez. “This is really hurting everyone as releasing new games/apps is not recommended right now because you just get stuck in the rankings.” The thread created a number of responses from angry and frustrated developers. “I’m astonished by the lack of answers and the poor stability of the system,” said one developer.

Microsoft appears to be struggling to fix the issue, one developer who wishes to remain anonymous shared the following email with WinRumors from a Microsoft support person:

We have not been able to locate the contacts that own the rankings process but are escalating this issue. The issue is getting considerable attention in the forums as we have seen, but is not part of the App Hub Marketplace program. Our escalation is intended to help push the rankings updates more often than they are now, or at least on a regular basis.

WinRumors reached out to Microsoft for comment but the company has not yet responded.

Update: Microsoft appears to have started to rectify the issue early on Tuesday morning according to several developers. Still no official word from the company on the two weeks of rank issues.