Do you have p7zip installed?

Created attachment 126901 [details]
Ark Modules

Ark Modules

 hard  ~  ls -l /usr/bin/7z
-rwxr-xr-x 1 root root 39 авг 10  2019 /usr/bin/7z

p7zip-full/focal,now 16.02+dfsg-7 amd64 [installed]
p7zip-rar/focal,now 16.02-3 amd64 [installed]
p7zip/focal,now 16.02+dfsg-7 amd64 [installed]

When create tar.gz - all is ok for selected folder
When create 7z - not
But i check for empty folder, and try archive it - all is ok. Maybe this is p7zip bug.
I try found why my folder not archived.

I found why archive not created:
If exit link in folder (content) as example:
 hard  …  wineTMP  prefix  dosdevices  ls -l
итого 0
lrwxrwxrwx 1 hard hard 10 мар 20 10:01 c: -> ../drive_c
lrwxrwxrwx 1 hard hard 10 мар 20 10:01 com1 -> /dev/ttyS0
lrwxrwxrwx 1 hard hard 10 мар 20 10:01 com10 -> /dev/ttyS9
lrwxrwxrwx 1 hard hard 11 мар 20 10:01 com11 -> /dev/ttyS10
lrwxrwxrwx 1 hard hard 11 мар 20 10:01 com12 -> /dev/ttyS11
lrwxrwxrwx 1 hard hard 11 мар 20 10:01 com13 -> /dev/ttyS12
lrwxrwxrwx 1 hard hard 11 мар 20 10:01 com14 -> /dev/ttyS13

Or any other links

 hard  …  wineTMP  prefix  drive_c  ls -l
итого 24
lrwxrwxrwx  1 hard hard   20 мар 20 10:01  Games -> ../../game_info/data
drwxrwxr-x  3 hard hard 4096 мар  8 16:34  ProgramData

If i remove it all is ok, archive created.

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

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If you have already provided the requested information, please
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Thank you for helping us make KDE software even better for everyone!

New information was added with comment 5; changing status for inspection.

(In reply to Konstantin from comment #4)
> When create tar.gz - all is ok for selected folder
> When create 7z - not
> But i check for empty folder, and try archive it - all is ok. Maybe this is
> p7zip bug.
> I try found why my folder not archived.

Can't reproduce this with ark-21.12 and p7zip-16.02 or 7-zip-21.07.
Could you pack this folder directly by 7z from the command line (this what ark would do):
7z a -l archive.7z folder_with_links

Does it succeed?

Duplicate of multiple of various reports around involving files 7z / p7zip can't handle.

Typically the issue is with symbolic links, and comment 5 showing even just "com1 -> /dev/ttyS0" is a quite likely candidate for problems as /dev/ttyS0 would be attempted to be added to the archive which would fail and would get whined about in the output of 7z, but then Ark swallows that error output, leading to the mess.

For anyone finding this by accident later, this is why 7z isn't used universally and tar is still being used despite its significant limitations. The 7-Zip project mostly focuses on Windows, and support for features not presented or not really used there is poor, so it either gets upset with some files, or worse case it makes an archive that unpacks into a mess different than what was intended to be archived, like symbolic links being replaced with the files they pointed to.
The problem with Ark is not just the lack of error propagation, but even hiding the error.

Reaping this as it went without additional info for long, and there are multiple similar enough bug reports anyway.

*** This bug has been marked as a duplicate of bug 453452 ***