Replaces by regular expressions

I have tried to replace some text by regular expression and I don't know how can I do it this replacement:

Find:(dwg)$
Replace: $1 c:\\\\tmp\\

Regular expr [x]

Even I have written the double backslash there is still tabulator in the replaced text. It means that the result seems like this:

drawing.dwg -> drawing.dwg c:\ mp\

I have tried used tripple backslash too and it doesn't work.

Could you look at it?

I have solve this issue by the second replacement \t by t