Note Learn about the fix for this problem for Windows 7 and Windows Server 2008 R2.

Symptoms

Assume that you use Microsoft Office 365 on a computer that's running Windows 8, Windows 8.1, Windows Server 2012, or Windows Server 2012 R2. When you use Microsoft Outlook to connect to Office 365 Exchange servers, Outlook displays a "Trying to Connect" or "Disconnected" status for a time period of five minutes to an hour or more.

Cause

This problem occurs because individual function calls in the remote procedure call (RPC) over the HTTP connection take a long time to return. Additionally, these calls pile up under heavy-load scenarios. This pile-up situation causes the call-return process to take even longer.

Resolution

Hotfix information

A supported hotfix is available from Microsoft Support. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix. Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, go to the following Microsoft website:

http://support.microsoft.com/contactus/?ws=supportNote The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

For Windows 8 and Windows Server 2012, there are no prerequisites to apply this hotfix.

For Windows 8.1 and Windows Server 2012 R2, you must first have update 2919355 installed.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any previously released hotfix.

The English (United States) version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows 8 and Windows Server 2012 file information and notesImportant Windows 8 and Windows Server 2012 hotfixes are included in the same packages. However, only "Windows 8" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 8" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.

    Version

    Product

    Milestone

    Service branch

    6.2.920 0.17 xxx

    Windows 8 and Windows Server 2012

    RTM

    GDR

    6.2.920 0.21 xxx

    Windows 8 and Windows Server 2012

    RTM

    LDR

  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows 8 and Windows Server 2012" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.

For all supported x86-based versions of Windows 8

File name

File version

File size

Date

Time

Platform

Rpchttp.dll

6.2.9200.17103

141,824

03-Sep-2014

02:48

x86

Rpchttp.dll

6.2.9200.21219

141,824

03-Sep-2014

02:34

x86

For all supported x64-based versions of Windows 8 and Windows Server 2012

File name

File version

File size

Date

Time

Platform

Rpchttp.dll

6.2.9200.17103

188,928

03-Sep-2014

02:22

x64

Rpchttp.dll

6.2.9200.21219

188,928

03-Sep-2014

02:37

x64

Rpchttp.dll

6.2.9200.17103

141,824

03-Sep-2014

02:48

x86

Rpchttp.dll

6.2.9200.21219

141,824

03-Sep-2014

02:34

x86

Windows 8.1 and Windows Server 2012 R2 file information and notesImportant Windows 8.1 and Windows Server 2012 R2 hotfixes are included in the same packages. However, only "Windows 8.1" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 8.1" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.

    Version

    Product

    Milestone

    Service branch

    6.3.960 0.16 xxx

    Windows 8.1 and Windows Server 2012 R2

    RTM

    GDR

    6.3.960 0.20 xxx

    Windows 8.1 and Windows Server 2012 R2

    RTM

    LDR

  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows 8.1 and Windows Server 2012 R2" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.

For all supported x86-based versions of Windows 8.1

For all supported x64-based versions of Windows 8.1 and Windows Server 2012 R2

For all supported ARM-based versions of Windows 8.1

Additional file information for Windows 8 and for Windows Server 2012

Additional files for all supported x86-based versions of Windows 8

File name

Package_1_for_kb2958752_bf~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

1,768

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Package_1_for_kb2958752~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

2,471

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Package_2_for_kb2958752_bf~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

1,765

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Package_2_for_kb2958752~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

2,468

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Package_for_kb2958752_rtm_bf~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

1,894

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Package_for_kb2958752_rtm~31bf3856ad364e35~x86~~6.2.1.0.mum

File version

Not Applicable

File size

1,929

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

Update-bf.mum

File version

Not Applicable

File size

1,753

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

X86_79681487c1c76bd39a787c5192380cd2_31bf3856ad364e35_6.2.9200.21219_none_bc1d11ef9902885e.manifest

File version

Not Applicable

File size

696

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

X86_c18741e4b032a317fda099bfa10313c0_31bf3856ad364e35_6.2.9200.17103_none_94063b7f0a69706d.manifest

File version

Not Applicable

File size

696

Date (UTC)

04-Sep-2014

Time (UTC)

02:26

File name

X86_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.17103_none_9cf95d53107ad4e3.manifest

File version

Not Applicable

File size

8,745

Date (UTC)

03-Sep-2014

Time (UTC)

03:12

File name

X86_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.21219_none_9d7e2bee299b28a8.manifest

File version

Not Applicable

File size

8,745

Date (UTC)

03-Sep-2014

Time (UTC)

03:17

Additional files for all supported x64-based versions of Windows 8 and Windows Server 2012

File name

Amd64_6bdde905b916e55ca8a348f527ed3189_31bf3856ad364e35_6.2.9200.21219_none_74ae11ab0ddccf5f.manifest

File version

Not Applicable

File size

700

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_79681487c1c76bd39a787c5192380cd2_31bf3856ad364e35_6.2.9200.21219_none_183bad73515ff994.manifest

File version

Not Applicable

File size

698

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_bbca7a70a3d4fd49f9f9873195695632_31bf3856ad364e35_6.2.9200.17103_none_0b941b9aa327ed04.manifest

File version

Not Applicable

File size

1,040

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_c0427c38d5e984d9979b8906ea6d7ebe_31bf3856ad364e35_6.2.9200.21219_none_e58bf045e293e124.manifest

File version

Not Applicable

File size

1,040

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_c18741e4b032a317fda099bfa10313c0_31bf3856ad364e35_6.2.9200.17103_none_f024d702c2c6e1a3.manifest

File version

Not Applicable

File size

698

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_e1d5a7a57a6bcb7a54332b7e8a308878_31bf3856ad364e35_6.2.9200.17103_none_17e5f343ab4aa058.manifest

File version

Not Applicable

File size

700

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Amd64_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.17103_none_f917f8d6c8d84619.manifest

File version

Not Applicable

File size

8,749

Date (UTC)

03-Sep-2014

Time (UTC)

05:14

File name

Amd64_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.21219_none_f99cc771e1f899de.manifest

File version

Not Applicable

File size

8,749

Date (UTC)

03-Sep-2014

Time (UTC)

21:32

File name

Package_1_for_kb2958752_bf~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

2,220

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_1_for_kb2958752~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

4,092

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_2_for_kb2958752_bf~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

2,209

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_2_for_kb2958752~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

4,079

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_3_for_kb2958752_bf~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

1,983

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_3_for_kb2958752~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

2,910

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_for_kb2958752_rtm_bf~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

2,820

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Package_for_kb2958752_rtm~31bf3856ad364e35~amd64~~6.2.1.0.mum

File version

Not Applicable

File size

2,881

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

Update-bf.mum

File version

Not Applicable

File size

2,411

Date (UTC)

04-Sep-2014

Time (UTC)

02:28

File name

X86_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.17103_none_9cf95d53107ad4e3.manifest

File version

Not Applicable

File size

8,745

Date (UTC)

03-Sep-2014

Time (UTC)

03:12

File name

X86_microsoft-windows-rpc-http_31bf3856ad364e35_6.2.9200.21219_none_9d7e2bee299b28a8.manifest

File version

Not Applicable

File size

8,745

Date (UTC)

03-Sep-2014

Time (UTC)

03:17

Additional file information for Windows 8.1 and for Windows Server 2012 R2

Additional files for all supported x86-based versions of Windows 8.1

Additional files for all supported x64-based versions of Windows 8.1 and Windows Server 2012 R2

Additional files for all supported ARM-based versions of Windows 8.1

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

References

Learn about the terminology that Microsoft uses to describe software updates.

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