If you are trying to post a journal and getting an error that you are missing a dimension, but it is active in your Sage Intacct instance and also appears to be active for other assets in your register, there may be a few things you missed when importing the affected assets.
When importing assets into AssetAccountant for the first time, it is VERY important you exactly match your classifications/dimensions in your import to what is in Sage Intacct.
For example, location and LOCATION will be treated as two separate dimensions. Even capitalization at the start of the word matters.
Further, you may not have synced dimensions for the particular assets in Sage Intacct.
Make certain that you Sync your Classifications and make sure that every instance of the dimension is mapped to Sage Intacct.
For example if your Dimension is Location, make sure all the locations (E.g. New York, Dallas, Boise, Birmingham) are synced and exactly match between AA and Sage Intacct.