no body from the staff?

From what version have you been upgrading?
What third party modules do you have?
Third party theme?

1 - From what version have you been upgrading: Upgrade From DNN_Platform_9.3.1.2_Upgrade.zip to DNN_Platform_9.3.2.24_Upgrade.zip

2 - What third party modules do you have: Only Module Installed 37921_0_AdvancedBizMap_06.09.00_Install.zip

3 - Third party theme: yes

Note on windows event viewer i see the next error when this error is showed:

Event code: 3012

Event message: An error occurred processing a web or script resource request. The resource identifier failed to decrypt.

Event time: 9/17/2019 2:07:09 PM

Event time (UTC): 9/17/2019 6:07:09 PM

Event ID: b7600a7fd9b04f1bbb6d92a4358bac97

Event sequence: 1285

Event occurrence: 12

Event detail code: 0

 

Application information:

    Application domain: /LM/W3SVC/1/ROOT-1-132131934161848308

    Trust level: Full

    Application Virtual Path: /

    Application Path: X:\path\domain.com.do

 

Process information:

    Process ID: 2708

    Process name: w3wp.exe

    Account name: IIS APPPOOL\domain.com.do

 

Exception information:

    Exception type: CryptographicException

    Exception message: Error occurred during a cryptographic operation.

   at System.Web.Security.Cryptography.HomogenizingCryptoServiceWrapper.HomogenizeErrors(Func`2 func, Byte[] input)

   at System.Web.UI.Page.DecryptString(String s, Purpose purpose)

   at System.Web.Handlers.AssemblyResourceLoader.System.Web.IHttpHandler.ProcessRequest(HttpContext context)

 

 

 

Request information:

    Request URL: https://www.bdi.com.do:44...t=635875365181218729

    Request path: /WebResource.axd

    User host address: XX.XX.XX.XX

    User: 

    Is authenticated: False

    Authentication Type: 

    Thread account name: IIS APPPOOL\domain.com.do

 

Thread information:

    Thread ID: 54

    Thread account name: IIS APPPOOL\domain.com.do

    Is impersonating: False

    Stack trace:    at System.Web.Security.Cryptography.HomogenizingCryptoServiceWrapper.HomogenizeErrors(Func`2 func, Byte[] input)

   at System.Web.UI.Page.DecryptString(String s, Purpose purpose)

   at System.Web.Handlers.AssemblyResourceLoader.System.Web.IHttpHandler.ProcessRequest(HttpContext context)

Welcome to the DNN Community!

no body from the staff?

DNN is an open source project, and this site is a "community" website. The "staff" would be other good folks like you who hang out in these forums and other places to provide support, to develop the product, etc. But nobody is "staff."

There are a number of organization who are capable of providing paid support, if that is what you need. Many of those you'll find here do that, too.

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As for your question, how are you trying to get to the "document manager"? Do you really mean Site Assets from the Persona Bar?

Are there any errors reported in the Persona Bar's Admin Logs (formerly known as the Event Log)?