WCF - Access Denied when creating folder - wcf

Question

I've built a WCF service and want to host it on IIS. One of the features I want is to programmatically create a subfolder in the WCF webhost root, to persist some json files.I've tested it on my local dev IIS Express and it works fine, which is no surprise 'cause I have all the necessary permissions.Now, I want to publish it on my public domain. For this, I've created a subdomain on Plesk and a subfolder within httpdocs. I've copied the web.config file and the Bin folder from my dev machine to this folder on my domain. But, when I enter the svc url on my browser I get a access denied exception (the folder is created in a dependency injected in my service, that's why I get the exception at this point).
Server Error in '/' Application.
Access to the path
'C:\Inetpub\vhosts\««my domain»»\httpdocs\VersioningService\Repository' is
denied.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.UnauthorizedAccessException: Access to the
path
'C:\Inetpub\vhosts\««my domain»»\httpdocs\VersioningService\Repository' is
denied.
Below is my web.config:
<?xml version="1.0"?>
<!--
For more information on how to configure your ASP.NET application, please visit
http://go.microsoft.com/fwlink/?LinkId=169433
-->
<configuration>
<system.web>
<compilation debug="false" targetFramework="4.5" />
<httpRuntime targetFramework="4.5" />
<customErrors mode="Off"/>
</system.web>
<system.serviceModel>
<serviceHostingEnvironment aspNetCompatibilityEnabled="false" multipleSiteBindingsEnabled="true">
<serviceActivations>
<add factory="VersioningService.Services.ManualMajorMinorVersioningHostFactory"
relativeAddress="~/ManualMajorMinorVersioning.svc"
service="VersioningService.Services.ManualMajorMinorVersioning" />
</serviceActivations>
</serviceHostingEnvironment>
<behaviors>
<serviceBehaviors>
<behavior>
<serviceMetadata httpGetEnabled="true" />
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
</configuration>
This is what I use to get the current assembly path:
var assemblyFolder = Path.GetDirectoryName(Assembly.GetExecutingAssembly().CodeBase);
Note: If I use the ProgramData folder I get NO exception, but I would prefer to have a subfolder within the WCF folder.
This is clearly a permissions issue. Do I need to add something else to my web.config?Do I need to ask my host provider to give some extra permissions to some user?