So in our SharePoint 2016 On-Premise environment where I work we are still heavily reliant on InfoPath at this point in time. Plans are to find an alternative that gives the functionality and desired look and feel as per communications. We rebooted the servers on Sunday due to another issue that arose with an issue of communication between the SharePoint and one of the nodes in the SQL Cluster.
Currently there have been two errors that shows up. One is stating that the custom code cannot be ran. The other is that it is not able to load the form. The custom code is relatively simple over all, as it is a university with multiple locations it grabs the users location and auto fills in a field based on said location and sets another field in some cases based on where the form is hit from. IE incident for IT or Request or Training for one form in particular. This custom code is used in both Document libraries and lists. Prior to this past weekend it was all working as intended.
After the WFEs were rebooted on this last Sunday trying to troubleshoot the issue with communication to the SQL the next day these forms that all had a custom code described above started to have issues working giving one of two issues to the user. The correlation IDs for these even in Verbose mode basically amounted to stating that the Sandbox code service was busy and was unable to process the code requested. Today we had to do another reboot as per a request from MS to install WireShark to be ready to gather packets for our SQL issue. Since doing this reboot currently any form with this custom code always errors out regardless. It used to be about a 40/60-50/50 chance for it to work. Which had suggested that the possible motive was perhaps the Applications servers as we could hit the same server and get different results. When we rebooted the servers the Application servers were not touched in the process, only the WFEs. Fortunately the forms are only internal issues, as we also have our external site on the same farm, (I know not the best practice but was setup this way before I got here and not my decision to change.)
Even now the errors still amounts to the same as before where it is saying that the Sandbox code service is unavailable and timed out. These two errors are pretty prominent as a whole. There is also a few other errors that seemed to suggest that turning off CustomErrors would give further information, the message stating simply that it failed. I turned off the CustomErrors and even still after everything the ULS logs still posted the same for the CID.
If we remove the code, the form works. So we know it isn't the form and even on a test form we have that uses much of the same code it fails to suggest that a change to the Lists in question haven't happened leading to undefined fields in the coding.
This issue has happened before in the past and was not the first time that it occurred. My hope is to come up with a method or fix that will be more permanent so we don't have to worry about running into this issue again, though my hopes ultimate is to talk the teams using forms like this to get a better method or using a more modern form tool like PowerApps w/Flow or some third party tool to accomplish said tasks for the forms upon opening.
I am a SharePoint Admin on the boxes so have the ability to accomplish any tasks as needed. Hopefully any fixes that can be done would be a relatively simply accomplishment as we have a change review process for major changes that takes a lot of effort to fix this.
