Not sure I tried the following

```
>> exist('script.m', 'file')

ans =

     2

>> run('script')            
Error using run (line 56)
script not found.
 
>> run('script.m')
Error using run (line 56)
script.m not found.
 
>> run(fullfile('.', 'script.m'))
Error using run (line 51)
./script.m not found.
 
>> script
success
```