LKBEN10701: HowTo: configure sizelimits for *.pst- (and *.ost-) files in Outlook 2003 and up

Symptom

Unable to move Items in Personal Folders in Outlook

Cause

Maximum filesizes, resp. configurable limits

Solution

Possible Error Message:
Can't move the items. The file path\filename.pst has reached its maximum size. To reduce the amount of data in this file, select some items that you no longer need, and then permanently delete them

Mailbox Cleanup wizard may launch

Watch out:
There are differences between files in ANSI- and UNICODE (mentioned below)!
The maximum limit of *.pst- and *.ost-files in ANSI-format will be 2GB and cannot be extended by the following keys.
The "WarnFileSize"- and "WarnLargeFileSize" registry entries will not generate user warnings! Once the warning level is reached, no file size growth is permitted (therefor no mails can be received, sent, moved or copied; AutoArchive function will fail; compaction function is triggered), however, the physical size may still increase due to internal processes.

Registry Policy Location:
HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\11.0\Outlook\PST
(11.0: Outlook 2003; 12.0: Outlook 2007)

Registry Location:
HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\PST
(11.0: Outlook 2003; 12.0: Outlook 2007)

Registry Keys (all REG_DWORD):

• MaxLargeFileSize
  UNICODE (new Large format)
  Range: 0x00000001 – 0x00005000 (equals 1-20480MB in 1MB increments)
  Default: 0x00005000 (equals 20GB)
  Values greater than Valid Range: possible, but not recommended due to performance decrease
• WarnLargeFileSize
  UNICODE (new Large format)
  Range: 0x00000000 – 0x00005000 (equals 1-20480MB)
  Default: 0x00004C00 (equals 19GB)
  Values greater than Valid Range: possible, but not recommended due to performance decrease
  Should always be at least 5% below "MaxLargeFileSize"
• MaxFileSize
  ANSI (earlier Outlook format)
  Range: 0x001F4400 – 0x7C004400 (equals 1,95-1984,01MB in 1Byte increments)
  Default: 0x7BB04400 (equals 1,98 GB)
  Values greater than Valid Range: will be ignored
• WarnFileSize
  ANSI (earlier Outlook format)
  Range: 0x00042400 – 0x7C004400 (equals 0,25-1984,01MB in 1Byte increments)
  Default: 0x74404400 (equals 1,86 GB)
  Values greater than Valid Range: will be ignored
  Should always be at least 5% below "MaxFileSize"

Disclaimer:

About the Author

Author: Wim Peeters - Keskon GmbH & Co. KG

Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience, including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform.