.QDLX File

The QDLX file extension is associated with Quicken, a personal finance management tool developed by Intuit, Inc, which is available in both Windows and Mac Versions.

The *.qdlx files were used by some version of Quicken for Mac , probably to store some sort of financial data.

How to open:

Generally speaking, program specific accounting files can only be used in their respective programs. However, you can often export to some exchange format that should be widely supported .For general information try to look at:Basic info how to open accounting and tax files

How to convert:

Most of financial and accounting file types can be exported to OFX or QFX format, or even CSV (Comma Separated Value) format. For general information try to look at:Basic info how to convert accounting and tax files