This is usually because the Default Web Site’s (or the site in which the syncfusion virtual dirs are installed) “Application Protection” is set to “Low”. It should instead be “Medium” or “High”.
To change this:
If it’s set to low, then you cannot run apps using the 2.0 framework if the default web site is configured to use 1.1 (which we assume is the case in this m/c) – that would result in the “It is not possible to run two different versions of ASP.NET in the same IIS process” error you have encountered.
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