> Source: [sk171707](https://support.checkpoint.com/results/sk/sk171707)

# sk171707 - "SslVersionOrCipherMismatch" error when disabling AES128 and opening a new Log tab

| Property | Value |
|----------|-------|
| Solution ID | sk171707 |
| Date Created | 2021-01-25 |
| Last Modified | 2024-11-26 |
| Technical Level | Advanced |
| Products | SmartConsole |
| Versions | R81.20, R81.10 (EOS), R81 (EOS) |
| OS | Gaia |

## Symptoms

- * "`SslVersionOrCipherMismatch`" error when disabling AES128 (as described in [sk182231](https://support.checkpoint.com/results/sk/sk182231)) and opening a new Logging \& Monitor tab in SmartConsole.

* SmartConsole debugs shows:  
  ``
  System.ArgumentNullException: Value cannot be null.``  
  ``
  Parameter name: s``  
  ``
  at System.IO.StringReader..ctor(String s)``  
  ``
  at System.Xml.XmlDocument.LoadXml(String xml)``  
  ``
  at InvestigatorGui.RequestCreator.a(ResponseDelegate A_0, Int32 A_1, String A_2)``  
  ``
  [1] [DATE TIME,PID] (ERROR) CP.Infrastructure.PersistencyHelperBase`1[[AppShellUI.TabbedPageContainer, AppShellUI, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]] - Could not create a persistent value``  
  ``
  [1] [DATE TIME,PID] (ERROR) SmartViewWrapper.View.SmartViewControl - Error loading page:https://IP/smartview/embedded/#view-id=00000000-0000-0000-0000-A69BF720DA43&locale=en-US, msg:SslVersionOrCipherMismatch.``  
  ``
  [1] [DATE TIME,PID] (ERROR) InvestigatorGui.RequestCreator - Xml Parse error``  
  ``
  ...``  
  ``
  [1] [DATE TIME,PID] (ERROR) CP.Infrastructure.PersistencyHelperBase`1[[AppShellUI.TabbedPageContainer, AppShellUI, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]] - Could not create a persistent value``  
  ``
  [1] [DATE TIME,PID] (ERROR) SmartViewWrapper.View.SmartViewControl - Error loading page:https://IP/smartview/embedded/#view-id=00000000-0000-0000-0000-A69BF720DA43&locale=en-US, msg:SslVersionOrCipherMismatch.``
* TLS1.0, TLS 1.1 and SHA1 are disabled (refer to [sk178505](https://support.checkpoint.com/results/sk178505)).

## Cause

Disabling AES128 while also disabling TLS 1.0, TLS 1.1, and SHA1 leaves no supported ciphers for establishing a secure connection, and is not supported. AES128 is required in conjunction with other cipher settings for a secure connection to function.

## Solution

This solution requires authentication. Please log in to view the full solution.

---

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