Troubleshooting

File Size Issues

Converted file is too large or too small

Cause: Unit mismatch between source and target formats.

Solution: Check the unit settings in the format options. DXF in particular is unitless — 10 units could mean 10 microns, 10 mils, or 10 millimeters. Set the correct unit interpretation in Tools → Options → DXF Import/Export.

Output file is unexpectedly large

Cause: Hierarchy was flattened during conversion, duplicating geometry.

Solution: Ensure Flatten is not enabled unless you specifically need it. Check the output format options — some formats require flattening (e.g., Gerber).

Display Problems

Shapes appear unfilled

Cause: Fill mode is off, or the shapes are open polylines rather than closed polygons.

Solution:

Press Ctrl+F to toggle fill mode
If shapes remain unfilled, they may be open polylines. Use Edit → Highlight Broken Polylines (Ctrl+B) to identify them
Use Repair Open Polylines or Join Polylines to close them

Drawing appears empty after import

Cause: The geometry may be at a scale far from the origin, or on invisible layers.

Solution:

Press Ctrl+0 to zoom to fit all geometry
Check the layer panel — toggle all layers visible
If still empty, verify the import format and unit settings

Font Issues

Text displays with wrong font or as rectangles

Cause: LinkCAD cannot find the required SHX font file.

Solution: LinkCAD searches for fonts in this order:

LinkCAD program folder
Folders configured in Tools → Options → Fonts
AutoCAD font folders (if installed)

If the font is not found, LinkCAD falls back to the default TXT font. To map font names, create a lcad.fmp file in the program folder:

original_font;replacement_font
arial;txt
custom;simplex;0.8

The optional third value is a scale factor.

License Issues

Registration code is rejected

Ensure the code is entered exactly as provided (case-sensitive, 16–20 characters)
Verify that the Name and Company fields match what was used when the license was issued
If the license was already activated on another machine, use the license transfer procedure

Network license shows "Not Licensed"

Verify the shared folder is accessible: try opening \\SERVER\LINKCAD in Windows Explorer
Check that lclic.net is in the LinkCAD program folder on the client
Ensure the user has Full Control permissions on the shared folder
Check Help → About for the license status

Performance

Viewer is slow with large files

See Viewer Performance for optimization techniques.

Conversion takes a long time

For files with many small shapes, enable Merge Overlapping as a post-processing step to reduce shape count
Consider converting to a format that supports hierarchy (GDSII, OASIS) instead of flat formats (Gerber, CIF)