Exchange Properties Limits addition
Exchange is updating property size and count limits, effective in two phases from late September to late November 2024. Organizations must adhere to these new limits and prepare accordingly. Phase 1 includes limits for properties like CloudMSExchUCVoiceMailSettings, while Phase 2 includes CloudMSRtcPolicyAssignments, among others.

We’re making some changes to allowed size and count of values for various Exchange properties, here are the definition of the limits:
- Max length: Size of each value
- Max Count: Total count of values
When this will happen:
Changes will be applied in two phases between late September 2024 and late November 2024
How this affects your organization:
When this change takes effect, you will not be able to exceed the allowed limits
Starting late September 2024, we’re adding the following limits to these properties:
Phase1:
| Property | Max Length | Max Count |
| CloudMSExchUCVoiceMailSettings | 1123 | 20 |
| MSExchArchiveName | 512 | 20 |
| MSExchResourceMetadata | 1024 | 20 |
| MSExchSenderHintTranslations | 500 | 20 |
| ExchangeResources | 1024 | 20 |
Starting late November 2024, we’ll be adding limits to the following properties:
Phase 2:
What you can do to prepare:
Review the new limits and take action as appropriate for your organization.
| Property | Max Length | Max Count |
| CloudMSRtcPolicyAssignments | 128 | 45 |
| MSExchResourceSearchProperties | 1024 | 35 |
| CloudMSExchUserHoldPolicies | 40 | 1150 |
| MSExchExtensionCustomAttribute1 | 2048 | 750 |
| MSExchExtensionCustomAttribute2 | 2048 |
750 |
| MSExchExtensionCustomAttribute3 | 2048 |
400 |
| MSExchExtensionCustomAttribute4 | 2048 |
400 |
| MSExchExtensionCustomAttribute5 | 2048 |
250 |
| ValidationError | 948000 |
10 |
| ProxyAddresses | 1123 |
1200 |
Message ID: MC884017

HANDS ON tek
M365 Admin


