Here is scenario from HCM team:
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If a Canadian manager attempts to process their US employee's leave request, they receive a 500 Internal Service error (regardless of execution from portal screens or from the ECC webserver).
This appears to only be an issue with the Canadian manager, as I have successfully processed requests by another non-US manager for a US employee. This is not a portal issue (since it occurs regardless of execution from portal screens or from the ECC webserver), is not a security issue (I assigned SAP ALL security access to the Canadian manager and still got the error message), and is not a configuration issue (using the backend transaction in r/3 to access the leave request not via the SAP inbox, I was able to access and approve it).
Note: Canada doesn't use time functionality so they don't typically submit/approve leave requests, or enter time off, etc.
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So, although the manager has all the right roles, org structure, etc....could the fact that Canada doesn't use time functionality (have CATS entries, profiles, attendance types) be causing the above server error?