Yes thats a bug in ProviderController.cs, it can be fixed by adding two code changes ...

When checking for .xml files in the directory, return null if none are found (instead of throwing an exception), and secondly, when adding providers to the collection, dont add it if getProvider returns null...

        ProviderInfo getProviderInfo(string providerPath)
        {
            // ... etc
            else
            {
                // bugfix: return null if no providerinfo.xml was found, dont throw an exception - thats too harsh!
                        return null;
                        //throw new FileNotFoundException("No ProviderInfo.xml file was found in '" + providerPath + "'.");
            }
             // .... etc

        }

AND

        public ProviderController(StoreProviderType providerType, string modulePath)
        {
            // ...etc
       
            foreach(string folder in folderList)
            {
                virtualPath = providerPaths[(int)providerType].Replace("\\", "/");
                virtualPath += getTrailingFolder(folder);

                ProviderInfo providerInfo = getProviderInfo(folder);
                        // bugfix: only add provider info if not null
                        if (providerInfo != null)
                        {
                            providerInfo.Path = folder;
                            providerInfo.VirtualPath = virtualPath;
                            providerInfo.Type = providerType;

                            providerList.Add(providerInfo);
                        }
            }
            // ... etc
        }

Hopefully this fix will be in the next release :)

JK

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