Some users would prefer to have their company logo and powered by logo instead of Zoho Projects logo, which is displayed by default in the login page i.e when you try logging-in via your portal URL.

If you are one among the users, who wish to change the logo, go to settings -- company profile -- upload logo section and upload your company logo.

Similarly, go to settings -- company profile -- upload powered by logo section and upload the required powered by logo.

Here's a small note for you. Make sure that the logo, powered by logo you are about to upload is as per the specified dimensions.

John.