I have a 3rd party .pfx cert with known good password, as I've imported it several times elsewhere, including the opmanager product.

Desktop Central is saying "invalid password" (private key backup password).  So thinking my original password might be too complex, or too many characters, I re-exported the cert including private key and provided a simple 9 character password. 

Even the short no special character password is being rejected by Desktop Central on this .pfx cert backup.

I'm very good with certs, including various formats, can you tell me what restrictions Desktop Central might have for this password?