Re: Why can't I create a new creditor/supplier account?
Looks like an interesting issue with Analytical Accounting! Do you have it incorrectly installed?
However, go to SQL Server and locate a table called "PM00200" and try to type the vendor information at the SQL level, if it works then you will need to perform SQL Profiler trace and get the exact stored procedure that causes the error, and then try to replace the stored procedure from one of your working companies.
Otherwise if the operation failed to save -which is probably the case- at the SQL level then it will be a corrupted trigger at the PM00200 that prevents the data from being added, disable the trigger and the issue will be resolved, most probably it is an issue with a trigger called "aagTR_PM00200Ins".
Disabling the trigger is not the final answer, your partner must investigate and find out what was the reason behind not being able to work with analytical accounting along with vendors and try to fix this out.
Hope that this helps.