Hi ThomasStessl-3946,
What can be the reason or how can i detect the reason behind this problem (too many users? ACL to big in a list? ...)
The default connection pool size is 100. When we go to the connection pool to select a connection for reuse, we find that all connections are in use. In this case, it will wait for the Connection Timeout time. If during this time, it has been unable to get a reusable connection from the connection pool, the above error will be reported. The solution is as follows:
- Check whether all connections are normally opened and closed. Connections that are not closed cannot be reused. Most of the above-mentioned errors are caused by this reason.
- In addition, we can also modify the connection string to increase "Max Pool Size", for example, set it to "Max Pool Size"=200.
- Only in extreme cases, we can modify the connection string to cancel the connection pool. This certainly solves the problem, but it affects performance.
More information: The-timeout-period-elapsed-prior-to-obtaining-a-co, sharepoint-sql-db-blocking-issues
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BR,
Mia