recordset.upgrade add spaces in a textbox?

Something strange is happenning.
I have follwed the whole flow of the program step by step, and only after the execution of the .upgrade command, in the textbox, where I keep a list if filenames, appear a large number of spaces at the end of the list.

I have checked carfully and until the line before .upgrade the textbox does not have any trailing space.

I also though that somehow the .upgrade command converted the last char (vbCrLf) into those spaces, but it isn't.

Does anyone has any idea on what is causing it?

Thanks in advance
Ivan