ITS_UNRESOLVED_EXT_FUNCTION is an ABAP runtime error which you may come across when using or developing within an SAP system. See below for the standard details explaining what it means and how you can avoid or fix this runtime error.
Short Dump Classification: A - ABAP Programming Error
You can view further information about a runtme error by using transaction code ST22 which will show you this and all runtime erros that have happen in your SAP system.
Also check out the Comments section below to view or add related contributions and example screen shots.
If the error occurs in a non-modfied SAP template, you might be able to
find a solution in the SAP Notes system.
If you have access to the SAP Notes system, check there first using the
following keywords: ITS_UNRESOLVED_EXT_FUNCTION
<runtime parameter>
<runtime parameter>
Template interpretation terminated, runtime error.
Call transaction SE80 and check the HTMLB program.
In SE80, choose 'Internet Service' and navigate to the corresponding
template. Take the service, theme and template name from the path of
the template causing the error:
<runtime parameter>.
Remember to publish the corrected template on the 'INTERNAL' site in
order to activate the change.
Please see abap error for more details about the possible cause of this runtime error and how it could be avoided.
Function <runtime parameter>, which is defined in module <runtime parameter> according to HTMLB declare
statement, was not found and therefore could not be called. Check
whether the function definition exists. Check for spelling mistakes in
the function name and module name.
HTMLB example, error ITS_UNRESOLVED_EXT_FUNCTION:
`declare funcA() in "moduleA.html"`
`funcA()` <- error, funcA() not defined
Template <runtime parameter> has caused a runtime error in function <runtime parameter>. Cause of
error: Function <runtime parameter> in module <runtime parameter> not found.