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Is there a limit to the number of folders and views there can be in a Lotus Notes® database?
There is not a predetermined limit but the database is limited by the number of "handles" that can be used.
The number of handles is limited to 10,495.
Notes can run out of memory handles when creating the sitemap for the list of views and folders in a database.
It usually manifests itself in one of the following error messages:
In Notes 5.x:
"Maximum number of memory segments that Notes can support has been exceeded"
In Notes 6.x
"Insufficient memory - too many design elements (Desk Design Pool)."
If there are a very large number of folders in a given database Notes attempts to
allocate memory for each one of the folders and views while creating
a sitemap for them.
Eventually, Notes can fail to allocate enough memory as it can't track where all
the memory is (due to the limitation on the maximum number of handles).
The workaround would be to use a more reasonable or practical number of folders/views in the database.
Decreasing the length of the folder or view name can also resolve the issue.
In cases where the one of the above errors occurs you may not be able to open a Notes database.
For more details on this issue, as well as steps which will allow you to open the
database, refer to the second document listed in the Related Documents section below.