Photoshop extension returns: extension could not be loaded because it was not properly signed.

Hi there,

I'm developing an extension for Photoshop CC 2015 and after configuring everything right, it still returns "extension could not be loaded because it was not properly signed." when I try to open it. This happens to every other development testing extensions.

What should I do in order to not bump into this error? My manifest.xml is as follows:

1. <?xml version="1.0" encoding="UTF-8"?> 
2. <ExtensionManifest ExtensionBundleId="com.myscript.extension" ExtensionBundleName="MyScript" ExtensionBundleVersion="1.0" Version="5.0"> 
3.     <ExtensionList> 
4.         <Extension Id="com.myscript.extension" Version="1.0"/> 
5.     </ExtensionList> 
6.     <ExecutionEnvironment> 
7.         <HostList> 
8.             <Host Name="PHXS" Version="[16.0,16.9]"/> 
9.             <Host Name="PHSP" Version="[16.0,16.9]"/> 
10.         </HostList> 
11.         <LocaleList> 
12.             <Locale Code="All"/> 
13.         </LocaleList> 
14.         <RequiredRuntimeList> 
15.             <RequiredRuntime Name="CSXS" Version="6.0"/> 
16.         </RequiredRuntimeList> 
17.     </ExecutionEnvironment> 
18.     <DispatchInfoList> 
19.         <Extension Id="com.myscript.extension"> 
20.             <DispatchInfo> 
21.                 <Resources> 
22.                     <MainPath>./index.html</MainPath> 
23.                     <ScriptPath>./source.jsx</ScriptPath> 
24.                 </Resources> 
25.                 <UI> 
26.                     <Type>Panel</Type> 
27.                     <Menu>Extension</Menu> 
28.                     <Geometry> 
29.                         <MinSize> 
30.                             <Height>400</Height> 
31.                             <Width>400</Width> 
32.                         </MinSize> 
33.                         <Size> 
34.                             <Height>400</Height> 
35.                             <Width>400</Width> 
36.                         </Size> 
37.                     </Geometry> 
38.                     <Icons> 
39.                         <Icon Type="Normal">./icons/dark.png</Icon> 
40.                         <Icon Type="RollOver">./icons/dark.png</Icon> 
41.                         <Icon Type="DarkNormal">./icons/light.png</Icon> 
42.                         <Icon Type="DarkRollOver">./icons/light.png</Icon> 
43.                     </Icons> 
44.                 </UI> 
45.             </DispatchInfo> 
46.         </Extension> 
47.     </DispatchInfoList> 
48. </ExtensionManifest>

Thanks in advance