Windows Booting very slow after 2004 update ,

I running a laptop with single hard drive bay - in order to upgrade I would need to buy a 1TB SSD hard drive, which I cannot afford to do this year. 

Basically, tough luck from Microsoft.

Great, useful info from @LucianMinea. I did this on my desktop, that was suffering badly from horrible restart times, many instances of "Not Responding" stalls on browsers, office programs, and File Explorer itself, PLUS Task Manager showing very high System Interrupts for 10 to 15 seconds until it settled down, but still bursts form 6 to 12%.

After disabling the said services, everything went back to normal with retsart and boot times back to normal, and no "Not Responding" or other issues as mentioned above. The System Interrupts hog in Task Manager is NEVER seen now, and I only ever see around 0.1%

I can only conclude that there is a big conflict between the File Explorer interfaces, and the inter-related new Search and Search Indexing design that came in with 2004, along with the SysMain caching read/writes getting in the way.

NOTE: MUST also do a stop and change to manual on the Windows Media Player Network Sharing service too, IF running,  BEFORE stopping and disabling Windows Search service, as the dependency will slow down the stop of Windows Search, and risk a Blue Screen 133 bug-check in DPC_WATCHDOG.

I DO plan to change my systems to SSD at the end of the year, so should have even better performance, as he recomends.

Windows isn't becoming slower. That's a misconception !

I'm a programmer and I had (and still have) Windows 10 from it's first release. I've gone through all the updates and versions and the system kept it's parameters without exceptions.

Now I've installed v 2004, It's a fresh install because lately I've done some experiments with my PC and .... you get the picture.

The system has the same speed, with a slightly noticeable "pause" when you start a program or app than the 1909.

If you're still running on HDD, please change it immediately with an SSD.

Two things I've always done, right after a fresh install or major update of Windows:

1. Stopped and disabled SysMain service, or SuperFetch how it was called in early versions.
2. Stopped and disabled indexing service.

As a professional, I've never understood the role of SuperFetch (SysMain), other than keeping my drive bussy all the time. And the indexing service is just lame. I mean, if I don't know to organize and label my stuff it's my problem. That's my point of view, anyway.

Right after stopping SysMain, you drive will breath again. Trust me on this one.

IT WORKED !!!! Thank You! Thank you! Thank you!

Windows isn't becoming slower. That's a misconception !

I'm a programmer and I had (and still have) Windows 10 from it's first release. I've gone through all the updates and versions and the system kept it's parameters without exceptions.

Now I've installed v 2004, It's a fresh install because lately I've done some experiments with my PC and .... you get the picture.

The system has the same speed, with a slightly noticeable "pause" when you start a program or app than the 1909.

If you're still running on HDD, please change it immediately with an SSD.

Two things I've always done, right after a fresh install or major update of Windows:

1. Stopped and disabled SysMain service, or SuperFetch how it was called in early versions.
2. Stopped and disabled indexing service.

As a professional, I've never understood the role of SuperFetch (SysMain), other than keeping my drive bussy all the time. And the indexing service is just lame. I mean, if I don't know to organize and label my stuff it's my problem. That's my point of view, anyway.

Right after stopping SysMain, you drive will breath again. Trust me on this one.

It does work for me but only for one day, following start up , boot time is back to 50 seconds. I am using western digital green ssd Ryzen 3 2200g with 16gb ram

Here is what worked for me after the Windows 10 2004 update made two of my computers run as slow as molasses.

(1) Boot in Safe Mode

(2) Delete everything in the Windows prefetch folder.  The folder is usually at C:\Windows\Prefetch

(3) Reboot

Windows rebuilds the prefetch folder so deleting it will not do any harm.  However, if you feel squeamish about deleting it, then rename it and create a new, empty prefetch folder in its place.

I spent hours on the first computer before stumbling onto this.  When the Windows update, and slowness, hit the second computer I tried this fix first and it immediately sped up.

Hopefully, it will help you.