Do you end your exception messages with a period?

Q. Do you end your exception messages with a period?

From Best Practices for Exceptions^† on MSDN in the section "Creating and raising exceptions":

• Use grammatically correct error messages, including ending punctuation. Each sentence in a description string of an exception should end in a period. For example, "The log table has overflowed.” would be an appropriate description string.

And regarding possible feedback to the user via the the application user interface, the question includes:

...Could also be an issue in localized resource strings.

The MSDN article referenced above also states:

• Include a localized description string in every exception. The error message that the user sees is derived from the description string of the exception that was thrown, and not from the exception class.

Also, from Exception.Message Property^† at the beginning of the section "Remarks":

Error messages target the developer who is handling the exception. The text of the Message property should completely describe the error and, when possible, should also explain how to correct the error. Top-level exception handlers may display the message to end-users, so you should ensure that it is grammatically correct and that each sentence of the message ends with a period. Do not use question marks or exclamation points. If your application uses localized exception messages, you should ensure that they are accurately translated.

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^† .NET Framework 4.6 and 4.5

Yes I usually treat the exception messages as full sentences, ending them with a period.

However, the message in the exception is meant for the developer, and not the end user. It may very well be that the same underlying exception should result in two different messages for the end user, depending on the context in which the exception-throwing method was called.

You really should show less technical, more user friendly messages to the user.