Symptom:

When you try to change the Trust status and/or try to accept a VPN link request, a warning box pops up with the message:

"Another application is currently using the Secure Messenger Toolkit.
Try performing your operation again later"

Detailed Information:

In environments with very high mail volume, the activity of processing messages can lock the Secure Messenger Toolkit (essentially, this is a database deadlock) and you can get the message above.

Resolution:

You can work around this issue a couple of ways:

1. Stop the SMTP Relay service briefly, go back to Security Manager, and accept the VPN Link Request. Then start the SMTP Relay again.

OR

2. In Security Manager, go to Manage Certificates. Highlight the certificate that was received with the link request and edit its Trust properties so it is Explicitly Trusted. Manually create a domain record for this domain in the External folder. On the Domain Security tab of the new domain record, check the box for "use VPN for messages sent to this domain", then add the certificate for that domain.

Set other configuration options on the Domain Security tab as desired.

Additional Info:

This problem is corrected in version 4.6 and later.