Server Error in '/' Application. Operation is not valid due to the current state of the object

Question

Hi,

I used to enter in this website without any problem, but since 2 days now I am not able.

It gives me the following error

Why is giving me this error?

I would be very grateful if someone could gave me a clue to solve this issue

Thanks in advance

Regards

Answer 1

Hello @Roberto ,

Welcome to Q&A Forum!

We have same error during document uploading then apply following setting in web config file. please verify appSettings block properly added or not.

Please following steps:

1.Open IIS(Internet Information Services Manager) >> expand Sites folder >> select web application and right-click it >> click on Explore.

2.Can you check if your web.config is having this line else add this.

<appSettings>  
   <add key="aspnet:MaxHttpCollectionKeys" value="5001" />  
</appSettings>  

Note:You can back up the web.config file in advance to prevent other errors.

More information, please refer to this post.

• How to Resolve the Error : Operation is not valid due to the current state of the object.

Thanks,
Echo Du

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