# Valid index names **URL:** \ **Category:** Elasticsearch\ **Created:** [February 14, 2012, 7:12am UTC](https://discuss.elastic.co/t/valid-index-names/6699 "2012-02-14T07:12:17Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Eric\_Jain](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/eric_jain/32/834_2.png) [@Eric\_Jain](https://discuss.elastic.co/u/Eric_Jain)\ **Post date:** [February 14, 2012, 7:12am UTC](https://discuss.elastic.co/t/valid-index-names/6699/1 "2012-02-14T07:12:17Z")
It looks like elasticsearch doesn't allow mixed case index names. Is this a Lucene limitation, or an elasticsearch feature to protect Windows users? Not a big deal, just a minor annoyance for people using Base-36- encoded UUIDs for index names... ---
**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\ **Post date:** [February 14, 2012, 2:49pm UTC](https://discuss.elastic.co/t/valid-index-names/6699/2 "2012-02-14T14:49:40Z")
Its not a Lucene limitation (Lucene is not even aware of it). Yes, its mainly done to protect mixed cases problems with file systems. On Tuesday, February 14, 2012 at 9:12 AM, Eric Jain wrote: > It looks like elasticsearch doesn't allow mixed case index names. Is > this a Lucene limitation, or an elasticsearch feature to protect > Windows users? > > Not a big deal, just a minor annoyance for people using Base-36- > encoded UUIDs for index names... ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 3:39am UTC](https://discuss.elastic.co/t/valid-index-names/6699/3 "2017-07-06T03:39:21Z")