Hi @AndreaB_
What you’re seeing in the other Esri Community thread you linked below is similar in symptoms, but your case is different based on the error message. In your situation, the failure is happening when Python attempts to load certificates from the Windows certificate stores. It’s not failing at the certifi level (which you could essentially call ArcGIS Pro’s trusted certificate store).
A very important clue you mentioned is that the model runs fine when run manually, but fails only when executed as a scheduled task. Just to confirm: is the scheduled task running under the same Windows account you use when you log into the server machine?
Since I don’t get to log into Esri Community often, I’ll outline a few tests and assumptions that may help give you or others in the community a clue to narrow this down.
1. Test whether the issue is related to interactive vs batch logon
As a test, configure the scheduled task to "Run only when user is logged on", then stay logged into the server and let the task run. If it succeeds in this mode, this could suggest the issue exists between the difference in interactive vs batch logins.
Windows loads user profiles differently depending on logon type. Batch logins (used by Task Scheduler) often do not load the full user profile, which can affect the certificate stores that are available, or perhaps how it parses certificates.
2. Given this task used to work, look for recently issued certificates
Look for any new certificates that may have been created or imported. You’ll probably want to check two main areas (and you may need IT assistance):
a. Local Machine certificate store
On the ArcGIS Pro machine, open Start menu and in the search bar, type and open certlm.msc (local machine certificate store), then check for recently added certificates in:
- Personal
- Trusted Root Certification Authorities
- Intermediate Certification Authorities
b. Current user certificate store
On the ArcGIS Pro machine, open Start menu and in the search bar, type and open certmgr.msc (current user certificate store), and check the same folders. You can look at the 'Valid from' date of certificates to determine when a certificate was issued.
c. Additionally compare the 2 stores
Additionally, look for any differences, especially for certificates that only appear in the Current user store. If you find a certificate that is not needed, removing it may resolve the issue. If there is a certificate that looks important, it may be worth considering trying to move it from the Current user store to Local Machine store, where batch logins would have a higher chance of being able to parse it correctly.
3. Another useful test
Try running the same scheduled task on a different machine. If it succeeds there, compare the differences, particularly in the Windows certificate stores between the two machines.
