On random times (and random activity types) our workflows crash with the following error:
Collection was modified; enumeration operation may not execute.
Looking at the ULS logs (stack trace) the following Nintex internal functions are getting called:
Nintex.Workflow.Common.StringFunctionParser.Execute(String Input, SPWeb web) Nintex.Workflow.HumanApproval.Message.AddContextDataToString(String input, NWContextDataCollection data, Boolean escapeValuesForSql, Boolean decodeInput, Boolean allowSensitive, Boolean esc...)
The behavior is not stable so I can't tell how to reproduce this. It happens to very small or larger workflows. Any ideas?
We are using Nintex Workflow 2010.