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Error when running Web Report - 'Unable to serialize the session state'

When attempting to run a report in PME or SPM, the following error occurs:

Server Error in '/reporter' Application.

Unable to serialize the session state. In 'StateServer' and 'SQLServer' mode, ASP.NET will serialize the session state objects, and as a result non-serialized objects or MarshalByRef are not permitted. The same restriction applies if a similar serialization is done by the custom session state store in 'Custom' mode. 

Product Line:
StruxureWare Power Monitoring 7.0.x
Power Monitoring Expert 7.2.x

Web Applications

This issue is caused by having an incorrectly configured Session State in the IIS Virtual Roots. 


1) Open up IIS Manager.
Start > Control Panel > Administrative Tools > Intranet Information Services (IIS) Manager.
2) Expand the Tree on the left hand side to display the IIS Virtual Roots.
3) Click on the ION Virtual Root and then double click Session State from the main window. 

4) For the Session State Mode Settings, make sure "In Process" is selected. If not, select it and then click Apply in the upper right hand corner. 
5) Do the same for the 'reporter', 'IONReportDataService', 'Web' and 'WebServices" Virtual Roots. 
6) Close out of the IIS Manager and do an IIS Reset from the Command Prompt. (See FA211981 for instructions on doing an IIS Reset from Command Prompt). 

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