Question about saving a file in 300 dpi on Adobe Illustrator?

I was creating an image in Adobe Illustrator, and when I first started making it I made a new document with color mode CMYK and with 300 dpi. I went to save it and it saved under 72 dpi in RGB. I realized how it had saved and clicked save and then changed the settings to 300 dpi and saved it as the same file. Since I had already saved the same file before that to 72 is the file really 72 dpi instead? Did it save my file permanently as a true 72 dpi and will I have to start over?Question about saving a file in 300 dpi on Adobe Illustrator?
No, you won't have to start over.



DPI on a digital image does not really mean anything to how it is shown. DPI only matters if you either scan an image (where a high DPI will give you a high resolution image) or print one (where high DPI will make a smaller printout). So if your image won't be printed, you don't have to care about DPI settings.



If you do have to print it, don't worry. Changing the DPI should be as easy as just opening the file and change it. This won't alter the quality of the image (unless, of course, you save it with a lossy compression such as jpg).