Reader v.2017.009.20044 does not start

Running Win 10 Pro 64-bit CU. Installed Reader today but it will not start. Very vague error messages from Microsoft's MMC:

Fault bucket 108879442295, type 1

Event Name: APPCRASH

Response: Not available

Cab Id: 0

Problem signature:

P1: AcroRd32.exe

P2: 17.9.20044.25828

P3: 58e4302d

P4: StackHash_f9d1

P5: 0.0.0.0

P6: 00000000

P7: 4000001f

P8: PCH_DC_FROM_KERNELBASE+0x000E75D4

P9:

P10:

and

Faulting application name: AcroRd32.exe, version: 17.9.20044.25828, time stamp: 0x58e4302d

Faulting module name: unknown, version: 0.0.0.0, time stamp: 0x00000000

Exception code: 0x4000001f

Fault offset: 0x00e30d04

Faulting process id: 0x1a28

Faulting application start time: 0x01d2c37d2e36826c

Faulting application path: C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader\AcroRd32.exe

Faulting module path: unknown

Report Id: 9902b49c-9a8d-4029-b931-b94c340806c2

Faulting package full name:

Faulting package-relative application ID:

Norton AV and MalwareBytes both come up clean as does sfc /scannow.

These are the only errors recorded unless AcroRd32.exe has a crash reported.

Please help.

Thanks.