nopCommerce 4.0 always show install screen after publish

Follow this checklist and test each one. Make sure your RESTART the web server before testing any changes you make.

1. Make sure you have the following files in the following path:
..\App_Data\dataSettings.json

2. Make sure the file has valid data with a valid SQL connection string where CONNECTION_STRING is located

{
  "DataProvider": "sqlserver",
  "DataConnectionString": "CONNECTION_STRING",
  "RawDataSettings": {}
}

3. Check the permission on your ..\App_Data\dataSettings.json and make sure whatever process NopCommerce is running under has permissions to read and write to the file. You can find this information by right-clicking > Properties > Security.  

4. Make sure you do not have any caching or third party software running. Such programs can be behind in updating.

5. If none of these options work, then it's time to pull out the serious diagnostic tools.  Procmon is fairly easy to use, despite looking very complicated. EVERY web developer working with .NET should HAVE and KNOW how to use this tool.  It will save you hours of troubleshooting and its FREE!

You can download it and learn to use this free tool using the link below.  Add a Path contains "dataSettings.json" and start capturing the events right before going to your site's page.  It will tell everything you want to know, including whether the file was found or not.  

https://blogs.msdn.microsoft.com/chaun/2014/06/06/basic-steps-for-making-a-process-monitor-procmon-capture/

Solved: nopCommerce V4.0
1)Make sure you copy dataSettings.json and installedPlugins.json to APP_Data.
2)Restart your IIS Application Pool and reload your website. Installation window will not appear.

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