THE folder '\\SERVER1\dfsroot\a3soft\A3\' is not reachable

I have a bk task that change the user password I use to make the bk.

If I open the script file, the password is diferent in that job from others jobs and i use the same user to login and select the source folders.

If i change the script, the job runs ok but the script file is changed modifying the the line of password.
The next time, the job fails with the error below:

El archivo o carpeta '\\SERVER1\dfsroot\a3soft\A3\' no se puede encontrar.

this the correct paswword line of the *.tib.tis file:

****P6u*FQ33p1" username="***backup">

After run the job the line changes with more characters:

****P6u*FQ33p1*******" username="***backup">

any idea?

regards