As one Manassas official said, the software conversion was like attempting to change the wings on an airplane in flight.

HTE is a legacy in Manassas's City Hall: alternately a curse and a blessing for a city eager to modernize its computer software and face the specter of the millennium bug head on. In past weeks, frustration with the slow and complicated conversion came to a head, causing a fourth tax billing imbroglio and obliging HTE Inc. representatives to hasten up from Orlando to meet with city officials Wednesday.

The meeting was a lesson in what-ifs and should-haves, as told by Finance Director Pat Weiler, who recounted the history of the conversion since the effort began almost four years ago.

The main culprit in the conversion fiasco was a constantly shifting cast of actors within both Manassas and HTE. With changing project managers on both sides and a few key players missing, there was, by all accounts, not enough communication and oversight during the conversion.

As a result of HTE's missed deadlines and other missteps, Weiler said that she has not paid the company since last September. Manassas currently owes the software company $70,000, some of which will simply have to wait, Weiler said, until she is satisfied that HTE has completed the jobs it has been billing the city for.

Minus that $70,000, Manassas has another $70,000 left for the project, Weiler said, having already spent roughly $700,000 in the past 3 1/2 years on the conversion. City Manager Lawrence Hughes said he didn't know if that sum would be enough to finish the project, or what sort of reimbursement, if any, the city might request from HTE.

"We need work at this point more than cash," Hughes said.

How did it get this way?

At Wednesday's meeting, Weiler told the story. Manassas needed to upgrade its software in several departments. She described a conscientious and time-consuming search for the right software package, which began with market research back in October 1995 and took more than a year to complete. It involved more than 40 city staff members and a detailed ranking and weighting system that left Manassas with one clear winner: HTE.

In addition to Y2K-readiness -- which means the computer programs won't crash when the new year comes around -- HTE has a number of advantages. The city's previous tax system was written in-house, and its inefficiency often hit the information technology department hard, Weiler said. HTE can track purchase orders, check city departments' budgets before allowing any purchases and make tracking overtime in the police department easier.

But while HTE was the best among the software packages that Manassas considered, it was not perfect. Manassas wanted software that matched the needs of many departments: payroll, utilities and the general ledger, to name a few. And no package that fit the bill for these other departments also served the city's tax needs. Manassas knew the conversion would involve the company making changes to the software first.

The software segment that required the most work -- the taxes -- was, not surprisingly, the segment that ultimately caused the most problems. With the exception of one other department, the tax department was the only area requiring data conversion, and it was the data conversion that caused much trouble.

"Neither side realized how much data needed to be converted," said Bob Gosselin, HTE's vice president of marketing.

The company also underestimated the amount of work necessary to adapt its software to the requirements of Manassas, which is the first city in Virginia to use HTE's tax software. (A handful of towns in Virginia use HTE, but towns have different tax requirements than cities do, the company said.) And because its staff on the conversion experienced extremely high turnover, new employees were sometimes taking over with little familiarity with the project.

Manassas planned to switch to the new tax software in April 1998 so that it could send out real estate tax bills on the new system. But by April, Weiler said, she learned that HTE had not even begun the data conversion. City staff hustled into gear, managing to send bills out on the old software.

So Manassas moved its deadline for the switchover to September 1998. Right around that time, the city lost its own project manager for the second time, and Weiler -- in the midst of an audit -- was unable to fill in as she had before. Frazzled with other responsibilities, she agreed to let the city transfer over to the new software.

"In hindsight, I should have stopped" the switchover, Weiler said. "But at the time . . . we thought the project was far enough along in the implementation and conversion that it would be fine."

So the city went "live" with certain basic data missing or incorrect.

And the rest, as they say, is history. In September, personal property tax bills were delayed. Real estate tax bills were delayed in November. This past April, the due date for vehicle applications was pushed back. And because the commissioner of revenue's office has been playing catch-up, it has asked for permission to delay sending out personal property tax bills and decals for two months.

"We made some mistakes," said Jack Harward, HTE executive vice president and co-founder, on Wednesday night. "I'm going to stay in the loop on this to make sure we have the proper resources allocated" to Manassas's conversion.

HTE says it is committed to making the conversion work and has promised to establish a time line for the rest of the conversion. City staff will make a recommendation as to how to proceed at the July 14 meeting of the finance committee.

Hughes said he does not know what the city will do. And he doubts dropping the company would put the city in a better position.

"Changing horses at this point would be even more of an expense," he said.