Extensions Off startup delay: potential explanations

Virtual Memory file Jeff Moss believes it is due to the "VM Storage" file (created when virtual memory is enabled in the Memory control panel) being erased when you start up with Extensions off. Bryan Dulock concurs. We are skeptical of this one, as we believe we have seen this delay even with VM off and no VM storage file to delete.

Disk Cache Several readers (including Tom Hedges and Ken Peterson) suggested that it is due to the fact that the disk cache is disabled (as set from the Memory control panel) when you startup with Extensions Off, which then requires much more disk access.

Disk First Aid check Matt Neuburg speculates it could be due to Disk First Aid running at startup, something that ordinarily only happens after a system crash etc. if you have "Check disk if computer was shut down improperly" option enabled from the General Controls control panel. However, we could not confirm that the check actually runs.

"(Disabled)" folders shuffle Another reader suggested that the cause is the movement of extensions into the "Extensions (Disabled)" etc. folders. The reader contends that, prior to Mac OS 9 or some 8.x version, when you disabled extensions with the Shift key, they did not run at startup although they remained in the "enabled" folders. Judi Toohey concurs.