nopCommerce version: 4.2

Steps to reproduce the problem:
1. Deployed latest version of 4.2 to Windows web app running in Azure
2. Setup site to use Managed SQL instance running 8 proc, 32 GB RAM and install sample data.

Everything works great with 1 instance, I have done load testing where I have had 100,000+ requests handled in less than 5 min. However, once I scale the app out to two instances I start receiving HTTP 500 errors. I get errors like: Access to the path 'D:\home\site\wwwroot\Plugins\bin\Nop.Plugin.ExchangeRate.EcbExchange.dll' is denied.

After scaling out web application I have redeployed however that does not address the issue.

Note this is not specific to 4.2 as I can reproduce on 4.1 too with a totally separate app in a different Azure region/datacenter -- the only commonality is a HTTP 500 in both cases. Has anyone tried to get this to work??

As far as the HTTP 500 I am not getting much help from the detailed logs::

This error means that there was a problem while processing the request. The request was received by the Web server, but during processing a fatal error occurred, causing the 500 error.
http://go.microsoft.com/fwlink/?LinkID=62293&IIS70Error=500,0,0x00000000,14393

Note the error: 0x00000000