'MSExchangeMapiMailboxAppPool' crashes sometimes

Question

'MSExchangeMapiMailboxAppPool' crashes sometimes

Wouter 1

We have an Exchange 2019 server (CU10) running on Windows server 2019. It has about 800 mailboxes and a part of those mailboxes are accessed through Outlook (2016 / 2019) on RDS servers, so they run in online mode.

The issue we have is that sometimes (about 3 times a week) the 'MSExchangeMapiMailboxAppPool' application pool crashes. The application logs show:

A process serving application pool 'MSExchangeMapiMailboxAppPool' suffered a fatal communication error with the Windows Process Activation Service. The process id was '41584'. The data field contains the error number

All MAPI connections are dropped and at that moment any Outlook that runs in online mode freezes for a few minutes (not responding).

We run Sophos on the Exchange server and all exclusions recommended by Microsoft have been added and AMSI has been disabled as well.

Kael Yao 37,751 Reputation points Moderator

2021-09-30T07:25:59.097+00:00

Hi @Wouter

Besides this event, can you find other error or warning events generated at the time when the mapi application pool crashes?
And would a recycle of the application pool get rid of this issue?
Levin, Alex 1 Reputation point

2022-10-26T00:12:13.67+00:00

Hello all, I am wondering if anyone here has has a resolution or an update? We implemented Ex2019 earlier this year and are on CU12 with August and October SUs installed and Extended Protection enabled. We have only been running production since June'ish. We experience very similar things where our users using Outlook in online mode first noticed a slow down in client response to where their Outlook client became unusable. Through much pain I have isolated from where I believe MAPIHTTP connections coming from a certain location are what starts this. I have captured a dump of the w3wp process where the memory being used was up to 14Gb plus. This was our second incident, on our first one a w3wp.exe process was as high as 31GB . In understanding the difference now between a memory hang and a memory leak, this appears to be a memory hang. I know from troubleshooting that the w3wp process was associated with the MSExchangeMapiMailboxAppPool. One question, is it common for this app pool to have HTTP POST requests as long or greater than 800000msec in the 'Time Elapsed' column? Thank you in advance for anyone's help. We too are also experiencing 5011 errors in the System log due to some of the App pools.

5 answers

Your answer

Kael Yao 37,751 Reputation points Moderator

2021-09-30T07:25:59.097+00:00

Hi @Wouter

Besides this event, can you find other error or warning events generated at the time when the mapi application pool crashes?
And would a recycle of the application pool get rid of this issue?
Levin, Alex 1 Reputation point

2022-10-26T00:12:13.67+00:00

Hello all, I am wondering if anyone here has has a resolution or an update? We implemented Ex2019 earlier this year and are on CU12 with August and October SUs installed and Extended Protection enabled. We have only been running production since June'ish. We experience very similar things where our users using Outlook in online mode first noticed a slow down in client response to where their Outlook client became unusable. Through much pain I have isolated from where I believe MAPIHTTP connections coming from a certain location are what starts this. I have captured a dump of the w3wp process where the memory being used was up to 14Gb plus. This was our second incident, on our first one a w3wp.exe process was as high as 31GB . In understanding the difference now between a memory hang and a memory leak, this appears to be a memory hang. I know from troubleshooting that the w3wp process was associated with the MSExchangeMapiMailboxAppPool. One question, is it common for this app pool to have HTTP POST requests as long or greater than 800000msec in the 'Time Elapsed' column? Thank you in advance for anyone's help. We too are also experiencing 5011 errors in the System log due to some of the App pools.

Answer 1

A few seconds before the application pool error I can see a few errors in the application logs in the eventviewer:

Source: MSExchange Common
ID: 4999

Watson report about to be sent for process id: 26864, with parameters: E12IIS, c-RTL-AMD64, 15.02.0922.013, w3wp#MSExchangeMapiMailboxAppPool, M.E.Data.Storage, M.E.D.S.CoreAttachmentCollection.OnAfterAttachmentSave, System.ArgumentException, 743f-dumptidset, 15.02.0922.013.
ErrorReportingEnabled: True

Source: ASP.NET 4.0.30319.0
ID: 1325

An unhandled exception occurred and the process was terminated.

Application ID: DefaultDomain

Process ID: 26864

Exception: System.Runtime.Serialization.SerializationException

Message: Type 'Microsoft.Exchange.Diagnostics.ExWatson+CrashNowException' in Assembly 'Microsoft.Exchange.Diagnostics, Version=15.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' is not marked as serializable.

StackTrace: at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter, SerializationBinder binder)
at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.Serialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter, SerializationBinder binder)
at System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck)
at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck)
at System.Runtime.Remoting.Channels.CrossAppDomainSerializer.SerializeObject(Object obj, MemoryStream stm)
at System.AppDomain.Serialize(Object o)
at System.AppDomain.MarshalObject(Object o)

Source: .NET Runtime
ID: 1026

Application: w3wp.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.ArgumentException
at System.ThrowHelper.ThrowArgumentException(System.ExceptionResource)
at System.Collections.Generic.TreeSet1[[System.Collections.Generic.KeyValuePair2[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]], mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].AddIfNotPresent(System.Collections.Generic.KeyValuePair2<Int32,System.__Canon>) at System.Collections.Generic.SortedDictionary2[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Add(Int32, System.__Canon)
at Microsoft.Exchange.Data.Storage.CoreAttachmentCollection.OnAfterAttachmentSave(Int32)
at Microsoft.Exchange.Data.Storage.AttachmentPropertyBag.SaveChanges(Boolean)
at Microsoft.Exchange.Data.Storage.CoreAttachment.Save()
at Microsoft.Exchange.RpcClientAccess.Handler.Attachment.SaveChanges(Microsoft.Exchange.RpcClientAccess.Parser.SaveChangesMode)
at Microsoft.Exchange.RpcClientAccess.Handler.RopHandler+<>c__DisplayClass120_0.<SaveChangesAttachment>b__0()
at Microsoft.Exchange.RpcClientAccess.Handler.ExceptionTranslator.TryExecuteCatchAndTranslateExceptions[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]
at Microsoft.Exchange.RpcClientAccess.Handler.RopHandlerHelper.CallHandler[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]
at Microsoft.Exchange.RpcClientAccess.Handler.RopHandlerHelper.CallHandler(Microsoft.Exchange.RpcClientAccess.Parser.IRopHandler, System.Func1<Microsoft.Exchange.RpcClientAccess.Parser.RopResult>, Microsoft.Exchange.RpcClientAccess.Parser.IResultFactory, System.Func4<Microsoft.Exchange.RpcClientAccess.Parser.IResultFactory,Microsoft.Exchange.RpcClientAccess.ErrorCode,System.Exception,Microsoft.Exchange.RpcClientAccess.Parser.RopResult>)
at Microsoft.Exchange.RpcClientAccess.Handler.RopHandler.GenericRopHandlerMethod(Microsoft.Exchange.RpcClientAccess.Parser.IServerObject, System.Func1<Microsoft.Exchange.RpcClientAccess.Parser.RopResult>, Microsoft.Exchange.RpcClientAccess.Parser.IResultFactory, System.Func4<Microsoft.Exchange.RpcClientAccess.Parser.IResultFactory,Microsoft.Exchange.RpcClientAccess.ErrorCode,System.Exception,Microsoft.Exchange.RpcClientAccess.Parser.RopResult>)
at Microsoft.Exchange.RpcClientAccess.Handler.RopHandler.StandardRopHandlerMethod(Microsoft.Exchange.RpcClientAccess.Parser.IServerObject, System.Func1<Microsoft.Exchange.RpcClientAccess.Parser.RopResult>, Microsoft.Exchange.RpcClientAccess.Parser.IResultFactory) at Microsoft.Exchange.RpcClientAccess.Parser.RopSaveChangesAttachment.InternalExecute(Microsoft.Exchange.RpcClientAccess.Parser.IServerObject, Microsoft.Exchange.RpcClientAccess.Parser.IRopHandler, System.ArraySegment1<Byte>)
at Microsoft.Exchange.RpcClientAccess.Parser.InputRop.Execute(Microsoft.Exchange.RpcClientAccess.Parser.IConnectionInformation, Microsoft.Exchange.RpcClientAccess.Parser.IRopDriver, Microsoft.Exchange.RpcClientAccess.Parser.ServerObjectHandleTable, System.ArraySegment1<Byte>) at Microsoft.Exchange.RpcClientAccess.Parser.RopDriver.ExecuteRops(System.Collections.Generic.List1<System.ArraySegment1<Byte>>, Microsoft.Exchange.RpcClientAccess.Parser.ServerObjectHandleTable, System.ArraySegment1<Byte>, Int32, Int32, Boolean, Int32 ByRef, Microsoft.Exchange.RpcClientAccess.Parser.AuxiliaryData, Boolean, Byte[] ByRef)
at Microsoft.Exchange.RpcClientAccess.Parser.RopDriver.ExecuteOrBackoff(System.Collections.Generic.IList1<System.ArraySegment1<Byte>>, System.ArraySegment1<Byte>, Int32 ByRef, Microsoft.Exchange.RpcClientAccess.Parser.AuxiliaryData, Boolean, Byte[] ByRef) at Microsoft.Exchange.RpcClientAccess.Parser.RopDriver.Execute(System.Collections.Generic.IList1<System.ArraySegment1<Byte>>, System.ArraySegment1<Byte>, Int32 ByRef, Microsoft.Exchange.RpcClientAccess.Parser.AuxiliaryData, Boolean, Byte[] ByRef)
at Microsoft.Exchange.RpcClientAccess.Server.RpcDispatch+<>c__DisplayClass49_0.<Execute>b__2()
at Microsoft.Exchange.RpcClientAccess.Server.RpcDispatch.ExecuteWrapper(System.Func1<ExecuteParameters>, System.Func1<Microsoft.Exchange.RpcClientAccess.RpcErrorCode>, System.Action1<System.Exception>) at Microsoft.Exchange.RpcClientAccess.Server.RpcDispatch.Execute(Microsoft.Exchange.Rpc.IProtocolRequestInfo, IntPtr ByRef, System.Collections.Generic.IList1<System.ArraySegment1<Byte>>, System.ArraySegment1<Byte>, Int32 ByRef, System.ArraySegment1<Byte>, System.ArraySegment1<Byte>, Int32 ByRef, Boolean, Byte[] ByRef)
at Microsoft.Exchange.RpcClientAccess.Server.WatsonOnUnhandledExceptionDispatch+<>c__DisplayClass32_0.<Microsoft.Exchange.RpcClientAccess.Server.IRpcDispatch.Execute>b__0()
at Microsoft.Exchange.Common.IL.ILUtil.DoTryFilterCatch(System.Action, System.Func2<System.Object,Boolean>, System.Action1<System.Object>)

Exception Info: Microsoft.Exchange.Diagnostics.ExWatson+CrashNowException
at Microsoft.Exchange.Diagnostics.ExWatson.CrashNow()
at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
at System.Threading.ThreadHelper.ThreadStart()

Source: Application Error
ID: 1000

Faulting application name: w3wp.exe, version: 10.0.17763.1, time stamp: 0xcfdb13d8
Faulting module name: KERNELBASE.dll, version: 10.0.17763.2183, time stamp: 0x8e097f91
Exception code: 0xe0434352
Fault offset: 0x0000000000039329
Faulting process id: 0x68f0
Faulting application start time: 0x01d7b51c6fb1ee51
Faulting application path: c:\windows\system32\inetsrv\w3wp.exe
Faulting module path: C:\Windows\System32\KERNELBASE.dll
Report Id: 0a62472a-6a07-48b1-9b7c-a19f297900c3
Faulting package full name:

We do not need to do anything to get it working again, it recovers itself (Outlook not responding for a few minutes during this time).

We use PRTG as monitoring and what I can see there at the time of the error:

MAPI connections drops to 0, has a spike after that and back to normal as it was before:

There is a spike in IIS Current Connections:

Additionally there is a increase of network traffic and CPU load.

Kael Yao 37,751 Reputation points Moderator

2021-10-05T09:35:49.843+00:00

Hi,
Thanks for the information.

I noticed you mentioned "IMAP connections drops to 0, has a spike after that and back to normal as it was before", do you also have clients using IMAP to connect to Exchange?

And does this issue always occur in this pattern: CPU and network traffic increase gradually and reach a point when the Mapi application pool crashes?
Wouter 1 Reputation point

2021-10-05T14:52:14.353+00:00

Sorry, that was a typo, it's they MAPI connections that are all dropped.

It is hard to judge what the order is, we use PRTG and the numbers I have a averages of 1 minute. But from what I can see it looks that the CPU load and Network peak happen after the application is crashed.

In the meantime I did uninstall Sophos and running with Windows Defender, but issue happened again.

Trying to create a dump with debug diag to see if that gives some information.
Kael Yao 37,751 Reputation points Moderator

2021-10-07T09:04:01.183+00:00

Thanks in advance for your update.

Answer 2

I did run Debug Diag, but while that is running it makes things worse (Outlook keeps hanging a lot) and the application pool seems to crash faster.

Anyway, I did get some logs, but didn't find any clue about a cause. There are various errors but for some I cannot find a lot of information online and for others Microsoft notes that these can be ignored.

A summary of Debug Diag:

EXCEPTION SUMMARY *
|-------------------------------------------------------------------------------------------------------|
| Count | Exception |
|-------------------------------------------------------------------------------------------------------|
| 284 | Microsoft.Exchange.Data.Storage.ObjectNotFoundException |
| 174 | Microsoft.Mapi.MapiExceptionNotFound |
| 68 | Microsoft.Exchange.Data.Directory.ValueNotPresentException |
| 58 | Microsoft.Exchange.RpcClientAccess.Server.LoginPermException |
| 53 | Microsoft.Exchange.Data.Storage.SaveConflictException |
| 53 | Microsoft.Mapi.MapiExceptionObjectChanged |
| 49 | Microsoft.Exchange.RpcClientAccess.RopExecutionException |
| 26 | Microsoft.Mapi.MapiExceptionNoAccess |
| 26 | Microsoft.Exchange.Data.Storage.AccessDeniedException |
| 15 | Microsoft.Exchange.Data.Storage.StoragePermanentException |
| 14 | Microsoft.Mapi.MapiExceptionPartialCompletion |
| 14 | Microsoft.Exchange.Data.Storage.PartialCompletionException |
| 10 | Microsoft.Exchange.Data.StoreObjects.DefaultFolders.Exceptions.DefaultFolderNoParentException |
| 6 | System.ServiceModel.CommunicationException |
| 4 | Microsoft.Mapi.MapiExceptionCallFailed |
| 4 | Microsoft.Exchange.MapiHttp.ContextNotFoundException |
| 3 | 0XE06D7363 |
| 3 | System.MissingMethodException |
| 3 | Microsoft.Exchange.RpcClientAccess.BufferOutOfMemoryException |
| 2 | Microsoft.Exchange.Collections.TimeoutCache.DuplicateKeyException |
| 2 | System.IO.IOException |
| 2 | Microsoft.Exchange.Data.Storage.Extensions.ExtensionNotFoundException |
| 2 | System.Net.Sockets.SocketException |
| 1 | Microsoft.Mapi.MapiExceptionNotInQueue |
| 1 | Microsoft.Exchange.Data.ServerLocator.ServerLocatorClientTransientException |
| 1 | Microsoft.Exchange.HttpProxy.Routing.Providers.ServerLocatorClientException |
| 1 | System.Reflection.TargetInvocationException |
|-------------------------------------------------------------------------------------------------------|

**** Some exception details were omitted due to the following reasons
The maximum number of stacks (MAX_CLR_EXCEPTION_STACKS_PER_EXCEPTION_TYPE = 10) for this CLR exception type have been collected: 'Microsoft.Exchange.Data.Storage.SaveConflictException'
The maximum number of total stacks (MAX_CLR_EXCEPTION_STACKS_TOTAL = 100) for all CLR exception types have been collected)
The maximum number of stacks (MAX_CLR_EXCEPTION_STACKS_PER_EXCEPTION_TYPE = 10) for this CLR exception type have been collected: 'Microsoft.Exchange.Data.Storage.ObjectNotFoundException'
The maximum number of unique messages (MAX_VARIANTS_PER_EXCEPTION_TYPE = 20) for this CLR exception type have been collected: 'Microsoft.Mapi.MapiExceptionNotFound'
The maximum number of stacks (MAX_CLR_EXCEPTION_STACKS_PER_EXCEPTION_TYPE = 10) for this CLR exception type have been collected: 'Microsoft.Exchange.RpcClientAccess.Server.LoginPermException'
The maximum number of unique messages (MAX_VARIANTS_PER_EXCEPTION_TYPE = 20) for this CLR exception type have been collected: 'Microsoft.Exchange.RpcClientAccess.RopExecutionException'
The maximum number of unique messages (MAX_VARIANTS_PER_EXCEPTION_TYPE = 20) for this CLR exception type have been collected: 'Microsoft.Mapi.MapiExceptionObjectChanged'
The maximum number of stacks (MAX_CLR_EXCEPTION_STACKS_PER_EXCEPTION_TYPE = 10) for this CLR exception type have been collected: 'Microsoft.Exchange.Data.Storage.PartialCompletionException'
The maximum number of unique messages (MAX_VARIANTS_PER_EXCEPTION_TYPE = 20) for this CLR exception type have been collected: 'Microsoft.Mapi.MapiExceptionNoAccess'
The maximum number of stacks (MAX_CLR_EXCEPTION_STACKS_PER_EXCEPTION_TYPE = 10) for this CLR exception type have been collected: 'Microsoft.Exchange.Data.Storage.AccessDeniedException'
The maximum number of unique messages (MAX_VARIANTS_PER_EXCEPTION_TYPE = 20) for this CLR exception type have been collected: 'Microsoft.Exchange.Data.Directory.ValueNotPresentException'

Debugging Overhead Cost:
Total Elapsed Ticks = 1145015 (100%)
Total Ticks Spent in Debugger Engine = 2140 (0%)
Total Ticks Spent in Crash Rule Script = 93675 (8%)
Successfully detached from process. The target process is no longer being debugged.
This instance of Dbghost will shutdown in a few seconds.

Note that the load of the Exchange server is not high, summary:

It has 12 cores (average load 40~60%)
80GB memory (average load 50%)
Storage is a Nimble all flash SAN
VMware cluster fully patched

In the meantime we are running CU11 and without Sophos.

I did run the Exchange Health Checker (https://microsoft.github.io/CSS-Exchange/Diagnostics/HealthChecker/) which showed all was good.

We have 4 DB's on seperate partitions (DB logs on seperate partition too), DB's are about 1TB in size. Could the DB size be a problem? We did have the same sizes on Exchange 2016 without issues. Read and write latency on the DB's is good (2 - 5 ms).

I saw another article online about garbage collection on IIS applications. When I check perfmon I can see that "MSExchangeServiceAppPool" has an average of 12% "% Time in Garbage Collection". I wonder if that could be an issue, as I could read that should be below 10%.

Regards,
Wouter

Kael Yao 37,751 Reputation points Moderator

2021-10-11T09:06:22.653+00:00

Hi Wouter.

Thanks for the information!

Could the DB size be a problem?

The best practice of database size for standalone Exchange server is 200GB or less.
While I think 1TB should also work fine and may not be the cause in this case.

I saw another article online about garbage collection on IIS applications.

I agree that it may more be a IIS related issue.
Wonder if manually setting the recycle schedule to have it recycled automatically in off-work time would help with this issue.
Wouter 1 Reputation point

2021-11-11T19:47:52.647+00:00

Sorry for the late reply, in the meantime we recycle the application pool every night, but that did not fix the problem either.

Still the application pool keeps crashing (average once a day), which causes Outlook to freeze for every Outlook user that is in online. Additionally some users report short Outlook "not responding" issues which can happen randomly a couple of times per day.

I'm out of ideas.

Answer 3

Piotr Stanczak 1

I have exactly the same issue on Exchange 2016 CU22, ~800 mailboxes most of them accessed in online mode.

I am really keen to know if there is any progress on that issue.

Regards
Piotr

Wouter Simons 1 Reputation point

2022-03-16T12:29:41.51+00:00

Hi Poitr,

We still have this problem, about a month ago a ticket has been created at Microsoft, but their response time is very slow. So far not a lot of progress.

They didn't take a look at the server or any logs yet and informed me that possibly the IIS load is high at certain moments for a specific virtual directory when the number of connected users is high. But that is unlikely as we have this issue at moments that the load isn't very high as well (like at Friday late in the afternoon where we see less connections). They suggested to add a secondary server, but I requested to keep looking for a solution for now.

I could not find any other people with this issue online, so I wonder if there might be some other simularity between your environment and ours. Are you able to provide details about your setup?

Regards
Wouter

Answer 4

Hi Wouter,

I have my own theory that the issue is related to online mode. I think that even if there is not a high load from users from the send/receive email perspective, every user click on the folder in Outlook or search is doing a lot of IIS connections because there is no cache. And I think this makes w3wp crash and after that Pool crashes.

I also have ticket with MS will see what will come out from it. I will keep this thread updated if I have anything useful to share.
Regards
Piotr

Answer 5

Bitbear 1

We are experiencing very similar issues on our Exchange On-prem server.

Our environment is also Exchange 2019 server (CU10) running on Windows server 2019.
Running with 8 cores avg around 15% usage, 96 GB memory avg 30%, 3 databases connected on an iSCSI disk avg 10% use time throughout the day. Approximately 300 mailboxes.

We are having the same errors show up including System > WAS 5011 Warning , affecting what seems like all Exchange related app pools frequently at different times through the day, as well as Application > MSExchange Common 4999 Error

Our users are reporting that Outlook is freezing/hanging or taking long times to load messages or search, as well as OWA becoming unavailable (not necessarily simultaneously).

I've also checked the following with no further success:
-run exchange health checker script > shows no problems
-exclude exchange folders/processes/file types from anti-virus scanning based on Microsoft's recommendations

I'm hoping we get some more responses here soon because I'm running out of ideas. I'll be sure to post if I make any progress though!

Wouter 1 Reputation point

2022-10-31T14:50:18.18+00:00

Looks like exactly the same problem.

As a workaround we are migrating customers to FSLogix so they can work with an OST file on the RDS environment, but that is quite some work as you need to disable UDP's and all users will get new profiles.

I've created a ticket at Microsoft over 6 months ago but there is zero progress. I get an update every month that they are working on it.
Piotr Stanczak 1 Reputation point

2022-11-01T10:35:15.137+00:00

Same here, we plan to move to FSLogix and switch to cache mode.
P.
Dean Engmann 0 Reputation points

2023-06-15T16:06:52.94+00:00

Were there any root causes figured out for this case, or can anyone tell me what was done to fix this?
Piotr Stanczak 1 Reputation point

2023-06-15T16:18:10.9+00:00

Unfortunately not. MS just suggestion to go to Cache mode.

Share via

'MSExchangeMapiMailboxAppPool' crashes sometimes

5 answers

Your answer