Let me assure both Microsoft engaged Support Engineer "experts" that there is a list of the 3498 files that the System File Checker knows about and if you were to make some effort to understand how SFC works you would see that msvcp100.dll is not in the
list.
That tells us that you have not recreated the problem and followed you own advice to "check if it helps" - which it won't.
You can find the 3498 SFC Files list here:
https://onedrive.live.com/?cid=EC673DF6F8DFEE84&id=EC673DF6F8DFEE84!109
If it is not in the list, Windows File Protection and therefore SFC doesn't know or care about the file - and let me assure you with 100% certainty that SFC will not replace missing files in the system32 folder which is where the file is supposed to be...
that is not how sfc /scannow works, that is not what it does and that is not what it is for.
Suggesting sfc /scannow is akin to saying "I have no idea what the problem is or how to fit it."
Another wild goose chase from the MS Answers "experts".