Issues with removing cygwin installed TTF font files

[Michael Soegtrop]

Dear Cygwin Team and Users,

since a few months I have issues deleting cygwin installations. In some 
cases randomly the /usr/share/fonts/microsoft folder and the TTF files 
in it remain. According to DOS dir the folder contains junctions to TTF 
files - not sure how this is possible - afaik a junction is for folders. 
But what I get is this:

C:\ci\cygwin64_21081_16603\usr\share\fonts\microsoft>dir
  Volume in drive C is SYSTEM
  Volume Serial Number is 70C2-07FA

  Directory of C:\ci\cygwin64_21081_16603\usr\share\fonts\test

02/07/2020  13:52    <DIR>          .
02/07/2020  13:52    <DIR>          ..
01/07/2020  11:47    <JUNCTION>     ahronbd.ttf [...]
01/07/2020  11:47    <JUNCTION>     andlso.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsa.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsab.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsai.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsau.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsaub.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsaui.ttf [...]
01/07/2020  11:47    <JUNCTION>     angsauz.ttf [...]
:

Interesting is that this does not happen always. I am working on a open 
source project and our CI installs and removes cygwin about 100 times a 
day. I see this issue about 20 times per month - distributed over all of 
our CI runners. Maybe Windows gives the TTF file some special handling 
every now and again, but I checked the registry and there is nothing 
pointing to this cygwin folder, except the cygwin installation registry.

I couldn't find any method to remove these files. I made sure I have 
delete rights and that nobody has a lock on these files, but still 
whatever I tried (Explorer, cygwin admin console, DOS admin console, 
reboot a few times, chkdsk, google) failed.

If you have an idea that could help me to delete these files reliably 
and/or avoid this situation, it would help me a lot!

Best regards,

Michael