DEM Download failure in EZ-InSAR

[anandsar01]

Select the DEM button show that Preparation of DEM is finished, but the MATLAB window shows the following error

I externally downloaded the DEM using dem.py command of ISCE and put that into the dem folder

However, LocalHostDEM is not detecting the DEM files and shows up DEM files have not been detected

[anandsar01]

I solved the problem by changing the permission using the command:
sudo chmod -R 777 [directory name]