C:\Keil_v5\ARM\PACK\.Web\NordicSemiconductor.nRF_Serialization.pdsc

[sunny]

C:\Keil_v5\ARM\PACK.Web\NordicSemiconductor.nRF_Serialization.pdsc (3474,74) Fatal Error parsing node '#text':unexpected end of input

[wlgrd]

Sounds like a corrupted pack. Try zip instead or delete and reload the pack from SDK