Spectrum Software
Industrial Strength Simulation




Spectrum Software has released Micro-Cap 11, the eleventh generation of our SPICE circuit simulator.

For users of previous Micro-Cap versions, check out the new features available in the latest version. For those of you who are new to Micro-Cap, take our features tour to see what Micro-Cap has to offer.




Questions and Answers - Spring 2011


Question: I installed Micro-Cap on my system. The program runs fine. However, when I exit the program, I receive error messages such as:

Permission denied 'WFB.BIN'.

What do I need to do about these errors?

Answer: The permission denied error occurs when Micro-Cap tries to perform an operation on the specified file, and the operating system states that the program does not have the proper permission to do that operation. There are two main causes of this.

1) The file or the folder that the file resides in is set to Read Only. If this option is enabled, the file is write protected so Micro-Cap is unable to modify the file. Any save operation will be prevented by the operating system.

In order to fix this, the Properties dialog box for the file or folder must be accessed through the Windows operating system. In the Properties dialog box, there should be an Attribute section that has a Read-only option. Disable this option. Depending on the configuration of your system, you may need Administrator privileges to do this.

2) Another program is already accessing the file and has placed a lock on it. In this case, you would need to find which program is accessing the file and then close the file or the program.

The reason that the Permission denied errors are occurring when the program is closing is that Micro-Cap will write to numerous files during the exit process. Micro-Cap stores the last used component and positioning information in all of the .CMP files that are loaded in the program. User preferences and settings are stored in the .DAT files, and the waveform buffer information in the WFB.BIN file is stored to the hard drive at this point.

All of these files are typically stored in the main Micro-Cap folder. If the Permission denied error occurs when exiting, make sure that the main Micro-Cap folder is not set to Read-only.

In Windows 7, Micro-Cap may also be setup to run as an administrator. This option can be enabled within the Compatibility tab of the Properties dialog box for the executable file. The Properties dialog box can be accessed by right clicking on the executable file in Windows Explorer and selecting Properties from the popup menu.

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