If you do not want to remove any of that content your only option is to manually disable the cache for some custom columns to get below the limit for cached columns in PostgreSQL:
Guide: Database CachingDisabling the cache will mean any statistics using them will have to be calculated on demand which may mean delays in the HUD. If you do not know how many custom columns you currently have click your Windows Start button then type the following:
pgadmin
and click on it when it appears. Double click on "PostgreSQL x.y" (where x.y is your PostgreSQL version) and if your prompted for a password the default is "dbpass" (without the quotes). Next double click on "Databases -> YOUR_DATABASE_NAME -> Schemas -> Public -> Tables -> cash_custom_cache (and/or tourney custom cache for tournaments) and the number in brackets is the number of custom columns which should look
like this.
Also please note that in some cases that number doesn't correlate directly to the number of cached columns which depends on the custom content you are using - you can see more about this in
this thread and
this thread.