podkaracz

You should consider going back to primary school where they will teach you how to read. It is clearly written that microsoft banned some keys if you want tool to be back just give them new keys.

With a delay of almost two months, Windows 10 1909 has been released, only for MSDN subscribers for now.
Hashes are available here:
https://www.heidoc.net/php/myvsdump_name.php?family=&name=Windows+10+(consumer+editions)%2C+version+1909
Downloads will be added to the downloader once released to the general public.

Okay no worries, thanks for trying. It is easy enough to modify the USB to maintain the OEM SLP.
I have been working on guides involving the Dell ISOs and have created in depth written guides and video instructions for Downloading the ISO and making a Bootable USB:
Download Dell Windows 7 Pro Multi-Lingual ISO (Media Refresh January 2016) from Dell and Make a Bootable USB Put together a list of the ISO checksums and details (still working on it),
Dell OS Recovery Tool ISO Checksums Made a slipstream script with DISM to bring them up to Media Refresh March 2019. The 32 Bit guide needs a bit of work still as I've mainly been focusing on the 64 Bit guide:
[64 Bit] Slipstream Updates (Media Refresh March 2019) and Drivers to the Dell Windows 7 Pro Bootable USB [32 Bit] Slipstreaming Updates (Media Refresh March 2019) and Drivers to the Dell Windows 7 Pro Bootable USB Converting the Edition from Dell Windows 7 Pro to Dell Windows 7 Home Premium. This conversion maintains Dell OEM SLP:
Convert Dell Windows 7 Pro Bootable USB to another Edition e.g. Dell Windows 7 Home Premium Removing all Dell OEM customisation to make a Microsoft Multi-Lingual, Multi-Edition Bootable USB for all other Retail and OEM Licenses. Instructs are also provided to provide OEM SLP for the other OEMs:
Convert Dell Windows 7 Pro Multi-Lingual Dell Bootable USB to a Microsoft Multi-Lingual, Multi-Edition Retail or non-Dell USB (Covering all Retail and non-Dell OEM Licenses) Finally converting the Slipstreamed Bootable USB back into an ISO for use with VMware:
Convert Updated Bootable USB to a ISO These set of guides should cover almost all languages and all editions of Windows 7 for both OEM and Retail licenses.

"This file is currently unavailable. Please check again later."

This change was done by Dell, not by me. Maybe the haven't uploaded the file yet. You could try again in a few days.

Nice, also don't forget you can build your own ISO image that match the original hash using CDIMAGE when the edition and language you need is missing.
Also, bit of spamming but here is my collection of Windows 7 ISO images downloaded from TechBench a few years ago. If anybody need it, send me a message.

Regards,
SnowBall
 
 

Probably. I had a huge list of service tags that I've been collecting since 2006 and I put them in one by one, 90% didn't work and non of them unlocks any Vista or XP. Really ond service tags won't work.
Downloading anything Pre-Vista from Microsoft for free is almost impossible... It would be good if some OEMs still have them for download. Anyway,  I am sure not a lot of people want to use the unsupported Vista and XP is just dying.
Now people should prioritize on Windows 7 and Office 2010 as the extended support will end soon. Who knows when Microsoft will take down all the Windows 7 downloads just like Office 2007. 

I tried about a dozen service tags found on Google. None of them worked. I suspect that MS no longer allows Dell to provide XP and Vista downloads.

I also have a few Windows XP Dell OEM images but not from service tags. I got them years ago and they are still sitting on my hard drive😁. The Windows 7 image was last updated in 2016... Unlikely Dell is going to update it...
Not sure if it is possible to find a service tag that could unlock Windows XP Downloads.
Regards,
SnowBall

@Philip Yip Maybe you can shed some light on this question?

Depending on what the Service Tag is... If it is for Windows 7, then no. If it is a new model released in 2019 with Windows 10 1809 or 1903 on it, possibly yes. I don't know much about Dell.
Regards,
SnowBall 

Are you sure there are updated iso files?
My understanding was that whenever Dell makes a new iso file available, it could be downloaded with existing service tags, but maybe I'm mistaken about that.
Anyway, if you provide a service tag that qualifies for a file that's not yet available through the tool, just let me know the tag, and I'll make an update available.

Here you go: https://software-download.microsoft.com/pr/Win7_Pro_SP1_Polish_x64.iso?t=9ce404c9-7ad9-4927-9cfd-258e3e60da29&e=1541951835&h=a57007d439518c31e8bdea462b34c638
It will work for only 24 hours, be quick.
Regards,
SnowBall

Tell me which ISO file/s you want to download and I can generate a link for you.
Regards,
SnowBall