Kerberos: White screen after login

Answer: The fact that a white screen is shown after a log-in attempt, and that the logfiles show messages about a too large header, show us that the HTTP header buffer on the TOPdesk webserver is smaller than the size of the request + your Kerberos ticket. There are 2 different solutions: 1) Increase the buffer 2) Decrease the ticket size Solution 1: The next steps need to be followed to increase the HeaderBufferSize of TOPdesk: - Stop the TOPdesk service - Go to the installation folder of TOPdesk and open the file 'webserver.properties' in an editor (e.g.

Answer: The fact that a white screen is shown after a log-in attempt, and that the logfiles show messages about a too large header, show us that the HTTP header buffer on the TOPdesk webserver is smaller than the size of the request + your Kerberos ticket. There are 2 different solutions: 1) Increase the buffer 2) Decrease the ticket size Solution 1: The next steps need to be followed to increase the HeaderBufferSize of TOPdesk: - Stop the TOPdesk service - Go to the installation folder of TOPdesk and open the file 'webserver.properties' in an editor (e.g. notepad or notepad++) Within this file you can find the following lines: ## The maximum request header size # webserver.headerSize = NOTE: the #-sign in front of the 'webserver.headersize' should be gone. In the case it isn't, this needs to be removed. Behind the 'webserver.headersize' you need to put a higher value than it is currently (in bytes). The following example sets the header buffer size to the maximum: ## The maximum request header size webserver.headerSize = 65536 Solution 2: For solution 2 the AD attribute of the TOPdesk kerberos user needs to be changed. By doing this, the ticket TOPdesk provides to the user will be stripped of irrelevant information (for TOPdesk). The attribute that needs to be changed (in an ADSI editor for example) is called 'userAccountControl'. The value of this attribute should be: 33620480 In the case the above steps do not fix the issue, it is best to contact TOPdesk support. Cause: The white screen can be caused by buffer overflow protection: When headers are generated that are bigger than the set header buffer size of TOPdesk. It can work for some operators/persons, while it doesn't work for others, because the length of the headers can be influenced by: the operations that are performed the browser that is used the group membership in Active Directory (name  and total number of groups).