Dynamics NAV - 'You do not have the following permission on Codeunit xxx::Execute'

Check your license details under "Object Assignment" and confirm what range your custom objects are allowed in.
50000 is the default, but it may not be the correct range if the customer has specifically purchased a different range.


Clear data from any tables that they are not registered for

http://help.lsnav.lsretail.com/Content/Installation%20Guide%20LS%20Nav/Clear%20Data%20Tables%20That%20Are.htm?Highlight=data%20license]


Before the customer’s license is activated in the database, it is necessary to check for and delete all data from tables that are not included in the license to prevent possible permission errors. This can be done by running the LS Retail Modules page that is located in the Administration menu.
The page shows what modules are available.  Select the Included in License field for the modules that are in the customer’s license, and click Check Data Usage on the Home action menu.
The system now counts entries in all LS Retail tables outside the modules included in the customer’s license.
Click Used Tables outside License to view the result of the check. This opens a page displaying a list of tables outside the modules included in the license. Click Clear data in the Actions menu to empty those tables. 
Note: This needs to be done for every company in the database.
The process can be repeated by clicking Initialize on the LS Retail Modules page.

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If this still does not work, open a support request with LS Retail specifically for license errors.
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