Authentication issue

Hello,

today i had the following problem:

I set up some switches at a new site and so i decided to choose another
radius-key as our usual. And i took one with 14 characters.
Now i see that the authentication works most of the time, but sometimes
i got the error message that radius-key is wrong:

An Access-Request message was received from RADIUS client NewSiteSwitch
with a message authenticator attribute that is not valid.

Is there any issue that IAS got problems with handling long or complex
radius keys ?
I just figured out that there can be problems with an ! at the end of
the radius key.

Thanks in advance

Eric

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