Attempting to change the category on an incident using the UpdateObject SOAP call results in an error:
SOAP Call payload
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://www.ca.com/UnicenterServicePlus/ServiceDesk">
<soapenv:Header/>
<soapenv:Body>
<ser:updateObject>
<sid>1302729930</sid>
<objectHandle>cr:400204</objectHandle>
<attrVals>
<string>category</string>
<string>pcat:51007</string>
</attrVals>
<attributes>
</attributes>
</ser:updateObject>
</soapenv:Body>
</soapenv:Envelope>
Result: Error setting attr 'category' on object 'cr:400204' to value 'pcat:51007'
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<soapenv:Body>
<soapenv:Fault>
<faultcode>soapenv:Client</faultcode>
<faultstring>Error setting attr 'category' on object 'cr:400204' to value 'pcat:51007'</faultstring>
<faultactor/>
<detail>
<ErrorMessage>Error setting attr 'category' on object 'cr:400204' to value 'pcat:51007'</ErrorMessage>
<ErrorCode>1003</ErrorCode>
</detail>
</soapenv:Fault>
</soapenv:Body>
</soapenv:Envelope>
While the above may present if the Category's pcat persid value is not valid, inactive, or inapplicable to incidents, did confirm that the category persid is valid, active, and applies to incidents.
Category change is working via REST web services or the classic web UI.
Service Desk Manager 17.4 RU2 to RU4
Known issue which presents when the specified category is configured for incident tickets only, and no other tickets.
Categories that are configured to apply for incidents and call requests do not exhibit this behaviour.
The fix for this issue will be included in the forthcoming 17.4 RU5 release (slated for late October/early November 2025)
See also related behaviour described in SOAP Category cr_flag, in_flag and pr_flag are not validated