Outlook sometimes hangs and does not update incoming email

[jgilbert2017]

(version 4.0.0.0)

I'm seeing some sporadic issues where Outlook hangs indefinitely and does not update incoming email.

The UI is responsive but the tray icon is stuck in the "updating" state and new mail does not show up.

Outlook will also hang on exit and need to be killed in the task manager to restart.

I've captured a memory dump and the hang is in VSTA_Main but the stack trace is just memory addresses (no method names/symbols). I'm not using any other plugins/addons other than outlookcaldavsynch.

How best to debug?

[Dim3nsioneer]

same issue here with V4.1.0

[jgilbert2017]

i still can't get a stack, but a possible hint indicates a file system operation failing (possibly due to excessive NTFS fragmentation???).

wish i could get a stack so the issue can be directly handling in the code, but for now i'm going to try cleaning up my disks and defragging to mitigate.

The following exception objects were found in the heap.
Name	Value	Type	Occurrence count
 
 {"Cannot access a disposed object."}		System.ObjectDisposedException	1
 {"The requested operation could not be completed due to a file system limitation "}		System.IO.IOException	1
 Message	The requested operation could not be completed due to a file system limitation	string	
 StackTrace		System.Diagnostics.StackFrame[]	
 InnerException	null		
 {}		System.Exception	1
 

[jgilbert2017]

after defragging i still got a hang. attaching a debugger to the running outlook.exe process does not give any stack or tasks :-(.

does anyone know if there is a flag / registry setting etc that will force outlook to host the vsto addin in a debug mode?

[jgilbert2017]

possible issue- SynchronizerFactory.CreateHttpClient does not set the Timeout property on the HttpClient. Tracing the code it looks like this is only used for timezone info fetching in GlobalTimeZoneCache but i suppose it could be a problem.

        private HttpClient CreateHttpClient(ProxyOptions proxyOptionsOrNull)
        {
            var proxy = proxyOptionsOrNull != null ? CreateProxy(proxyOptionsOrNull) : null;
            var httpClientHandler = new HttpClientHandler
            {
                Proxy = proxy,
                UseProxy = proxy != null
            };

            return new HttpClient(httpClientHandler);
        }

[jschiefer]

Seeing the same issue with 4.2.0, syncing with Nextcloud 23.