Installed the Simlink update this morning and found that it caused P3D V5.1 to crash as soon as a plane is loaded. Eventually disabled Simlink to Get P3D to start.
Found the following in the log file.
[2021-03-29 01:08:42] Navigraph Simlink Addon (v.1.1.20.0325) for P3D (x64) has loaded.
[2021-03-29 01:09:19] Status: 0; Last error: 183
[2021-03-29 01:09:19] Status: 0; Last error: 183
[2021-03-29 01:09:52] Status: 0; Last error: 183
[2021-03-29 01:09:52] Status: 0; Last error: 183
[2021-03-29 01:09:55] Status: 0; Last error: 183
[2021-03-29 01:09:55] Status: 0; Last error: 183
[2021-03-29 01:09:56] Status: 0; Last error: 183
[2021-03-29 01:09:57] Status: 0; Last error: 183
[2021-03-29 01:09:58] Status: 0; Last error: 183
[2021-03-29 01:09:59] Status: 0; Last error: 183
[2021-03-29 01:10:00] Status: 0; Last error: 183
[2021-03-29 01:10:01] Status: 0; Last error: 183
[2021-03-29 01:10:02] Status: 0; Last error: 183
[2021-03-29 01:10:04] Status: 0; Last error: 183
[2021-03-29 01:10:04] Status: 0; Last error: 183
[2021-03-29 01:10:05] Status: 0; Last error: 183
[2021-03-29 01:10:06] Status: 0; Last error: 183
[2021-03-29 01:10:07] Status: 0; Last error: 183
[2021-03-29 01:10:08] Status: 0; Last error: 183
[2021-03-29 01:10:09] Status: 0; Last error: 183
[2021-03-29 01:10:10] Status: 0; Last error: 183
[2021-03-29 01:10:11] Status: 0; Last error: 183
[2021-03-29 01:10:12] Status: 0; Last error: 183
[2021-03-29 01:10:13] Status: 0; Last error: 183
[2021-03-29 01:10:14] Status: 0; Last error: 183
[2021-03-29 01:10:16] Status: 0; Last error: 183