w7 64, 8.5.3 32 
 
I have repaired, and uninstalled/installed the MS visual c++ redistributable program. for w7 64.
 
And still the error persists.
 
=============
It works fine in Sonar 8.5.3 64 bit.
 
UAC is set to nought.
 
Ideas?

Did you repair, uninstall/install the 32 bit version of the same MS Visual C++ redistributable program?

Common sense would lead me to believe that the 64 bit version is for 64 bit programs (not necessarily the OS) and the 32 bit version is for 32 bit programs.

Yup, it's a 32-bit file so re-installing the 64-bit package would not install it.

I'd start by poking around on my disks and see if a copy exists that just isn't in the right place. If you find one, copy it into the system32 folder.

on the 32 win partition: 5.26mb 3/18/2010

on the 64 win partition: 4.16mb 1/07/2011

confusion reigns supreme

Why do you have separate partition for 32 and 64 bit. That's really not necessary. 

Dual boot: w7 -32 and w7 64.

Third partition on that drive will soon have w8 64.

On the 64 bit partition, I have Sonar 32 and 64 installed. Some "older" projects use a couple of 32 bit only plugins, hence the need.

It appears the mfc100u.dll file on the 64 bit install does not play well with Sonar 32.

So far it is only the plug-in manager that wants to use that file. Maybe I can avoid it. But I did want to import lots of presets exported from the 32 bit OS.

Will attempt installing the 32 bit file today.

mfc100u.dll file on the 64 bit install does not play well with Sonar 32

mfc100u.dll is also a dependency of 32-bit X1, but not 8.5, so "not playing well" is unlikely.
Installing the 32-bit VC++ redist package should fix your problem.

Installed the 32 bit redistrib and now the 32 bit plugin manager appears to work.

Thanks.

J

See, if you had just listened to me 4 days ago.

You assume I had time between then and now.