That is not an error, just and ordinary informative message. Most likely you have added a name mapping (or other project item) as existing item to another project so that they became referred to the same tcNM file, and you had several editors opened for the same name mapping from different projects, that's why while modifying it in first editor, second editor had to be refreshed, and TestComplete asked you to reload it.
Yes Pavel, i am sorry it's not error. But what does it do. It will overwrite the name mapping of shared project from where i added the login script.
I see that namemapppings for both projects are same and also if i add this login script to any third project, it is copying the whole name mapping that is exisiting for the shared project. Is that making it be overwritten by the new project according to what i develop