When the computer does not start, what exactly happens? Does the spinning gear endlessly spin? Gray screen stays? Blue screen stays? Please give as much detail as possible. Also, please tell us the model Mac that you have, amount of RAM, hard drive capacity and amount of free space on the drive. Anything else that might be relevant could be informative.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
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