The Application Pool behing Sitefinity is crashing on a regu

Hello everyone, the pool of my application is being recycled continuously ,in the event viewer to see this exception:

Message: Type is not resolved for member 'Microsoft.IdentityModel.Claims.ClaimsPrincipal, Microsoft.IdentityModel, Version = 3.5.0.0, Culture = neutral, PublicKeyToken = 31bf3856ad364e35'.

Someone can tell me what may be happening

It would be of help

regards

I have a few questions...

1. What version of Sitefinity is the site running?
2. Did you add, remove, and change any functionality to your Sitefinity site before this error started happening?
3. Did you make any setting changes just before this error started happening?

Any additional details you can provide will help.  Thanks.

Craig

Hello, the sitefinity version is 9.1. No changes have been made to the modules or site configuration.

regards

Edwin, do you have the recommended memory requirement for running a Sitefinity website?  

Sitefinity recommends 500+ MB of memory to run a Sitefinity website, but if you have more, use it.  You can read more about that at this URL... 

http://docs.sitefinity.com/deploy-projects-to-shared-hosting

Also, something I have done in the past is generate my own machineKey in the web.config file.  I have seen this used when Sitefinity is deployed in a shared web hosting solution.  Below is a great article from code project that will show you how to add this to your web.config.

https://www.codeproject.com/Articles/221889/How-to-Generate-Machine-Key-in-IIS

Let me know if either of these items will help.

Craig