You might have an Extension loading at start up that has issues, but without knowing what it is who can tell ?
What was it ?
As was said go to the hidden folder:
And move out the likely suspect “xxx.RB” and its subfolder.
Restart SketchUp to see what happens.
Alternatively go up one level in the above tree and rename your Plugins folder as ‘PluginsX’ - as it loads SketchUp will make a new Plugins folder and add in copies of its ShippedExtensions [su_… names].
If SketchUp doesn’t run with all of the other plugins moved then it’s another cause…
There are a number of other potential causes for SketchUp freezing.
Here are a few.
You did not install SketchUp by right-clicking the installer exe file’s icon and choosing 'Run as administrator…'
You have insufficient RAM available [unlikely]
Your Graphics Card drivers were auto-updated and it is clashing.
Check your GC control-panel and Device-Manager to try rolling-back to the previous driver version.