I am trying to enable an Account as a Partner Account, however, I am getting the following error message:
"Unable to Access Page"
The value of a parameter contains a character that is not allowed or the value exceeds the maximum allowed length. Remove the character from the parameter value or reduce the value length and resubmit. If the error still persists, report it to our Customer Support team. Provide the URL of the page you were requesting as well as any other related information.
Why do I get this message and what should I do to enable the Account into a Partner Account?
When you try to enable an Account as a Partner Account and any of the Contacts associated to that Account are owned by a Partner User, you would receive this error message. If Partner Account enabling was allowed to go through successfully in such a scenario, it could result in Partner Users owning Partner Contacts which is not allowed by design.
The only way to enable the Account as a Partner Account, when this situation is encountered, is to update the ownership of the associated Contacts so that they are owned by internal, non-Partner Users.
Note: Sometimes the error "Unable to Access Page", "Cannot Assign Portal Account or Contact to Portal User”, or "An error occurred while trying to update the record. Please try again. portal users cannot own partner accounts" can also be seen in this scenario.
See also
Create Partner Accounts
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