Index and length must refer to a location within the string

Hellow mates,
I do capture the logged on user and display their first name on my asp.net site.
I however need to make the first letter of the First name to be in UpperCase.

From the development PC my code works perfectly.
However after deploying on the server I get the error below.
Any workarround to achieve the same or that will help me solve my problem  will be highly apprecaited .


REgards,
elikat.
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Index and length must refer to a location within the string.
Parameter name: length
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code
Exception Details: System.ArgumentOutOfRangeException: Index and length must refer to a location within the string.
Parameter name: length

Source Error:


Lin ...