I am using Sitecore version : Sitecore.NET 7.2 (rev. 140526) and Web form version 2.4.0 rev. 140117.
At the time of installing Web Forms for Marketers I am getting below error :
An item name cannot contain any of the following characters: /:?"<>|-
I have removed the value for the InvalidItemNameChars setting but still I am getting the same error.
<setting name="InvalidItemNameChars" value="" />