1. Run the following query to find out if this is the cause of your problem. NOTE: If you are a SAAS customer, you will have to open a support case so the On Demand DBA's can run this query for you.
SELECT *
FROM PRJ_OBS_UNITS
WHERE NAME LIKE '%/%' OR
NAME LIKE '%:%' OR
NAME LIKE '%"%' OR
NAME LIKE '%''%' OR
NAME LIKE '%>%' OR
NAME LIKE '%<%'
2. If there are no results, this is not the cause of your problem. If results are returned, use those results to determine which departments need to be fixed and proceed with the rest of these instructions.
3. Change the invalid characters in department name and description to words or remove them.
4. Save the change(s).
5. Test to make sure the department can now be assigned to resources.
6. If that is successful you can test to see if adding the same character back in again will still allow you to assign the department to your resources successfully. If not, you will have to leave the character out.