<div>
Apple forums suggest this is a file permission problem with a suggested fix of running Disk Utility + Repair Disk, then reboot to see if problem has cleared.<br />
<br />
Only a real problem if Mac stops on blue screen.
</div>


Apple forums suggest this is a file permission problem with a suggested fix of running Disk Utility + Repair Disk, then reboot to see if problem has cleared.

Only a real problem if Mac stops on blue screen.

<div>
The problem only happened once, but thank you all for your contributions.
</div>


The problem only happened once, but thank you all for your contributions.

<div>
<div class="content wysiwyg-content">
Why does the MAC screen go suddenly blue, after I logged into it? Steps, I logged into the MAC, instead of seeing the usual desktop picture, I saw a blue screen for a few seconds.<br />
macOS 10.14.4
</div>
</div>


Why does the MAC screen go suddenly blue, after I logged into it? Steps, I logged into the MAC, instead of seeing the usual desktop picture, I saw a blue screen for a few seconds.
macOS 10.14.4

Why does the MAC screen go suddenly blue, after I logged into it?

Apple's early computers ran on a variety of operating systems, including a Pascal version and one based on CP/M, before releasing its ProDOS with the advent of its 16-bit computer. With the release of the Lisa, which had its own OS, Apple and computing entered the graphical age; it was followed by the Macintosh, which offered a series of "System" operating systems. Other Mac operating systems included PowerPC until Apple acquired NeXT and folded it into the Mac OS. Current operating systems for Apple devices are Mac OS-X and iOS.