The most common reasons for a delayed production are as follows:
Files are corrupt.
There are no manufacturing indications nor contain the following manufacturing specifications:
Sizes of holes and integrated positions
Dimensions (finishing slots, slotted holes, and anything unusual…etc.)
Material type and copper thickness of finished boards
Tolerance specifications.
Mismatch of Gerber files and manufacturing indications.
Undefined drilling or incorrect drilling
Drill files are missing
Drill files are missing tool list (ASCII text file).
Aperture list is corrupt or incomplete (Undefined D-codes)
Aperture list is missing. (Each file must have a D-codes with text files)
Gerber files are scaled (We require 1:1 size files)
Conflicting or missing right-reading information (Example: the orders of layers)
Thermal connections are missing on inner layers (Multi-layer)
Copper layers with no pads and/or no traces

Please keep in mind of the above to ensure smooth production flow. You may also wish to contact us for any manufacturing questions or concerns by submitting the correct files within two hours of your response to avoid delays in production.