1. Click Start, click Run, type regedit in the Open box, and then click OK.
2. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem
If the Maximum Allowed Sessions Per User entry does not exist, do the following:
On the Edit menu, point to New, and then click DWORD Value.
Type Maximum Allowed Sessions Per User as the entry name, and then press ENTER.
Right-click the Maximum Allowed Sessions Per User entry, and then click Modify.
Click Decimal, type the value that you want to set in the Value data box, and then click OK. (
Max Value is 36000)
Exit Registry Editor.
Click Start, click Run, type services.msc in the Open box, and then click OK.
Click the MSExchange Information Store service, and then click Restart Service.
Keep in mind, before making any changes in registry,
take the backup of the registry.
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