2687814 - Error "There is no signed manifest existing for OCS Package" in SPAM or SAINT

During an update on Support Package Manager(SPAM) and SAP Add-On Installation Tool (SAINT), the following errors can be seen in the DISASSEMBLE phase: 

Case 1

Import phase 'DISASSEMBLE' (<Date>, <Time>)
Verify the digital signature of OCS Package SAPK-10SAGINCTEFND
There is no signed manifest existing for OCS Package SAPK-10SAGINCTEFND (EPS file: I710020751258_0108128.PAT)
Abort the import due to an error situation (<Date>, <Time>)

Case 2

Import phase 'DISASSEMBLE' (<Date>, <Time>)
Unknown message with SAPKD74070
Unknown message with SAPKD74070 I710020751258_0122699.PAT
Interrupting import due to an error situation (<Date>, <Time>)
Displaying detailed information about error in phase 'DISASSEMBLE'
The import was canceled by the user
Import canceled due to an error situation (<Date>, <Time>)

• Support Package Manager (SPAM)
• SAP Add-On Installation Tool (SAINT)

signature verification, spam, signed manifest, W:TN:787 , KBA , BC-UPG-OCS-SPA , Support package tools for ABAP , Problem