how i can overcome this problem about the command save ?

Answer 1

[per isakson]

You try to save to C:\Program Files\MATLAB\R2012b\bin, which explains the error message.

Proposal

    save( 'c:\folder_with_write_permission\ABC.mat' )

or change current folder to a folder with write permission

Answer 2

[Image Analyst]

You can't save anything under the c:\Program Files folder or subfolders of it. That's just Windows' rule. Save it someplace else where you do have permission to save it.

Answer 3

[Star Strider]

I would create a specific .mat file and save to it instead:

save ABC.mat

to save everything in your workspace, or to save only those variables:

save ABC.mat A B C

See the documentation on save for details.