Reg File for Custom File Type Handler Program

Suppose instead of the default reg settings for, say, pdf files, one wants a reg file to set up a custom program handler.

For instance, Sumatra. One would like Sumatra to handle pdf files. When one double-clicks on a pdf file, Sumatra loads and shows the pdf file.

How would one set up a reg file to establish that?

As has been noted elsewhere, presently many are reporting that Windows seems to be switching our default program apps. So, in the pdf case, Sumatra is being switched to Edge. A reg file, then, to make the switch back would be greatly appreciated.

One can then study the requested reg file to use with other switched extensions as well.

Thanks,
Nicholas Kormanik

Welcome to the forum. Set pdf to sumatra then goto reg edit Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ApplicationAssociationToasts find the key and export it then you have your reg file

Did as suggested. Saved entire registry branch:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ApplicationAssociationToasts

Rebooted computer.

Instantly see what I'd earlier set up has been switched to what Microsoft wants. All reset.

Then I merged the saved 'customized' branch back into registry. Hoping to get back to the associations that I want.

No luck. Pdfs still load in Edge. As do epubs. Not Sumatra.
And web links bring up Edge as well, instead of Chrome.

Any other suggestions?

Thanks.

Did you save the key for sumatra or the whole branch?

Feel free to tell me to butt out but I can't duplicate this behaviour. Using Win 10 Home 1709 Build 16299.125 x64 I installed SumatraPDF 3.1.2 using the Use SumatraPDF as the default PDF reader option:


After installation, the usual nonsense notification appeared:


I used Start > Settings > Apps > Default apps > Choose default applications by file type to select SumatraPDF for PDF files.

Two restarts and a shutdown/restart later and the default PDF handler is still SumatraPDF.

I reset the VM afterwards and did exactly the same again... with the exact same results. SumatraPDF remains the default PDF handler.

dalchina said:

However there are plenty of reports of this sort of thing, mostly related to the use of Adobe products.

Ah, thanks. I avoid Adobe products if I can, hence why I haven't seen the issue before. I was just interested in case this was another 'MS knows best for you' across the board. :)

After searching and experimenting like crazy, I finally found one solution that seems to work. 97% of the Windows program associations problem solved!

Christoph Kolbicz is the wizard.

GetUserFTA
SetUserFTA
SetDefaultBrowser

Too complicated for me to explain. Go to his site and read about it.

http://kolbi.cz/blog/?p=433

Thanks to all of you for helping.

Nicholas Kormanik