Undefined function or variable

I don't understand why MATLAB stopped working properly, since today. I get error undefined function, for instance

imread loads a .png file ('40_tazza.png' locate inside frames cup). It's absurd since I have properly add the path (the folders are dark blue). I swear, it was working fine until yesterday. Please help

Answer 1

[Walter Roberson]

It looks to me as if your current directory might be "CG&3D" and that "CG&3D\Project2.0" might not be on your path.

[Alessandro Musi]

I did this

nothing's changed

Answer 2

[Alessandro Musi]

I solved, basically it was an external script that a friend of mine passed (copying from a toolbox) (angle2dcm). I simply copied the content of that script and pasted in a fresh new script (cleaning away the commented part, where the copyright was mentioned, don't think this made the difference, but still).