The following template is missing: sap

You are trying to use the Excel inplace functionality but ended up with below error message,

Some important notes from 1937247 – How to manage SAP standard templates [Video].

Only SAP_SM.xls and SAP_SM.xlsm is needed in the system from the SAP standard templates. (Sap_om.xls and sap_mm.xls files aren’t required anymore.)
Above SAP Basis 700 it is possible that templates exist only in CLIENT 000 and the business client can use them from there.
This is recommended by SAP. Mixed template uploading cause errors which means that if one template is uploaded to business client
the system will search every template there and won’t use them from client 000.
Template duplication causes error.

Solution

Step 1: Check for template duplicates.

In client 000, execute report BCALV_BDS_MAINTENANCE from transaction code SE38. Select option to list templates.

The output shown as below,

Step 2: Delete old templates.

Login to the client where you encountered the error message. Use report BCALV_BDS_MAINTENANCE and choose Unreferenced, Temporary and SAP_Standard_Templates under Delete templates.

Step 3: Upload new templates

Download the new templates from SAP Note 1686797 – ALV Excel: Signed SAP standard templates. Extract the zip file to your local desktop.

In client 000, use report BCALV_BDS_MAINTENANCE and choose Import templates. Select Transport Request if you plan to create and move the changes to other systems as well.