# Signing a .sis file

In S60 3rd Edition application development all `.sis` files must be signed before installing them to a device.

You can use the signsis tool delivered with the SDK to sign or unsign a `.sis` file. The signsis tool can be found in `<S60_SDK_installation_directory>\Epoc32\tools` and its usage is as described below:

    Usage: SignSIS [-?] [-c...] [-i] [-r] [-s] [-u] [-v] input [output [certificate key [passphrase] ] ]

    -? Output this information

    -c... Sign using specific algorithm: -cd for DSA, -cr for RSA

    -I Output licence information

    -o Report on content of sis file (after any other operation)

    -s Sign SIS file (requires sis file, certificate, key and passphrase)

    -u Remove most recent signature from SIS file

    -v Verbose output

    input The SIS file to be sign, unsigned or investigated

    output The SIS file generated by signing or unsigned

    certificate The certificate file used for signing

    key The certificate's private key file

    passphrase The certificate's private key file's passphrase

    You can generate SIS files using MakeSIS v4.

An example of how to use the private key and Self-Signed certificate. `<Path>` is the location where the private key and Self-Signed certificate are stored:

`signsis helloworldbasic.sis helloworldbasic.sis <Path>\<certificate>.der <Path>\<certificate>.key`

This will sign `<application_name>.sis` file.

Note that the created private key and the Self-Signed certificate are not encrypted and therefore no pass phrase is needed.

Now that you have created a `.sis` file and signed it, you can proceed to install it to an S60 device. This consists simply of moving the `.sis` file that you have created to your phone. This can be done through various different channels (WAP, e-mail attachment, infrared, Bluetooth, USB), depending on your PC and S60 device.

As the sending of a `.sis` file from your PC to an S60 device may vary on your PC and its capabilities, so, too, the receiving and installing of the application on your device may vary depending on your device.