Outlook says PST file reached maximum size limit
Solved Email & Outlook
BA
Barry Allen
November 12, 2019
2 replies
8,890 views
Reviewed by moderators

Outlook popped a warning that my PST reached its maximum size and now sending fails. I deleted a few thousand old emails but the file size on disk has not moved at all. What am I missing?

Accepted Answer
Verified by David Taylor, Community Expert ยท Reviewed November 2019

Two things going on. First, deletions in Outlook leave white space inside the PST rather than shrinking the file. Go to File then Account Settings then Data Files, open Settings on the PST and hit Compact Now. That reclaims the space.

Second, if the file sits near the 50GB ceiling even after compacting, split it. SysTools Split PST divides by year or size and keeps folder structure. Keeping your live PST under 10GB also stops the slow-Outlook complaints before they start.

Compact freed 12GB and the year split handled the rest. Sending works again. Solved.