When trying to get into HydraCAD, you get this error message.

Your HCAD_ENV.INI file is corrupted.
This is found in the \HES\HYDRACADWER50\PROGRAMS\VersionXx
folder where XX is the version you are using. Please copy this file from
a working machine and reopen HydraCAD or contact Hydratec for
assistance
 

All layers where objects should appear white in AutoCAD will randomly turn brown in color (colors 18, 19, 248, or 249)

Note the pipe dimension and main piping in the image above are brown instead of white.

File not found HydexVB3 Runtime Error 48 or Runtime Error 53 Runtime Error 50

When running the AutoCALC process, it hangs at step 2.4e "Re-Loading Calculated Data - AutoPeaking Data"

May also happen around steps 2.3, 2.4a, 2.4b, 2.4c, and 2.4d

When inserting a listing tag on a pipe, you get the error, "Invalid color number"

Double-Clicking on a riser nipple, or using the Edit Riser Nipple command (ERN) briefly displays the edit riser nipple dialog, which then closes

HydraLIST appears to not open, but appears on task bar.

You are not currently authorized to use this Hydratec Product.   Lack of authorization.

After attempting to download the Latest Toolbox, a warning appears saying the file cannot be opened. 
Tells user to delete toolbox .rvt file and try again, but that does not work. 

When clicking the Calculate button or the OK button from the Pre-Calc Questions window, you get a Runtime-error 5,

Run-time error '5': Invalid procedure call or argument