If you install AMPL somewhere in your home directory, you do not need to worry about the following.
If you use cloud licenses (e.g., AMPL Community Edition licenses), the AMPL folder cannot be read-only (e.g.,
"C:\Program Files\ampl.mswin64"). If really you want to have AMPL installed on a read-only folder, you need to set the environment
AMPL_LICFILE to a location where you store
ampl.lic and where you have permissions to write, and set
AMPLKEY_RUNTIME_DIR to a temporary folder.