Adding Custom Pictures to Acumatica Login Screen - Picture Size
You can replace the pictures / images that appear on the Acumatica login screen by replacing the files on the IIS web server.
The default location is:
C:\Program Files\Acumatica ERP\Icons
But your location might be different depending on where Acumatica was installed. Also, for Acumatica SaaS customers (most Acumatica customers are SaaS), I think you have to open a support case with Acumatica because they control the IIS web server (but I haven't done that personally).
The number of files seems to grow with each new Acumatica version. There are multiple files and the login screen cycles through them, that's how you get a different image each time you login to Acumatica. If you only want one image, just replace each file with the same image. I haven't tried this personally, but I believe you can also delete some of the default image files (since there are so many) to reduce the number images that the login screen cycles through.
The image files all start with login_bg (login_bg1.jpg, login_bg2.jpg, etc.):
If you open any one of those files, you can see that the dimensions are 1500x1000
So just replace those files with your own custom pictures and make sure each picture has the dimensions 1500x1000.
For Acumatica SAAS customers (and I think on premise as well) this is a neat way to do it by yourself.
If you only want one image, just replace each file with the same image. I haven't tried this personally, but I believe you can also delete some of the default image files
I have played around with this. The login screen will look at as many or as few pictures with "login_bg#.jpg" as their name in the folder. I haven't stressed the system to find the limit, but I have had over 30 before just to test with no problems. Just add more files and it will happily cycle through them all. The same idea, if you delete everything but bg1 and bg2, it will only cycle between these two.
We replaced those images locally & then couched it in a customization project for portability to a customer's SaaS instance. Really fun to do and makes such a difference at the client site! https://dquest.com/personalize-your-acumatica-login-page/